تويت
Caves of Maryland
The subject of this article and a reference book of the same name, Caves of Maryland was first released by the Maryland Geological Survey (MGS) in 1950. Information about Maryland caves was first gathered into a series of reports by Martin Muma in the mid 1940s, working under the MGS. After the release of these articles in 1946, a more comprehensive study was begun by William Davies, whose years of fieldwork led to the compilation of the premiere edition of Caves of Maryland in 1950[1]. Since its publication, this reference work has remained the principal source for information about Maryland caves, and has served as an outline for the work to follow.
Introduction
Following the release of the first edition of Caves of Maryland in 1950, several other attempts by various parties and interested groups have been made at expanding available information concerning Maryland's subterrain. In the late 1960s the MGS sponsored another statewide survey, undertaken by Richard Franz and Dennis Slifer, and a second, expanded edition of Caves of Maryland was released in 1971. It was not until the inception of this second project that areas west of Washington County were even thoroughly canvassed; even after the conclusion of the Franz/Slifer survey, it was speculated that even more, undiscovered caves could still remain in more remote portions of the western counties, prompting the need for an additional version, but since that time there have been no additional state sponsored reports or surveys released to the public.
In Maryland, a cave is defined as any subterranean cavity large enough for a human to enter[2]. This definition has led the authors to include several shelter caves, fissures, and mines that in states with larger, more complex cave systems, might otherwise go unlisted.
Locations
Cave locations are typically well-guarded secrets, as property owners are most-often fearful of liability issues and damage to their lands. Likewise, experienced spelunkers are also wary to guide novices to cave locations, fearing they might recklessly endanger the natural balance of these sanctuaries, making them inaccessible to all. While most find cave vandalism unimaginable, there are some who, whether of carelessness, malice, or ignorance, have hopelessly destroyed beautiful caves forever. For this reason, precise locations of caves are seldom published. Rather than using a coordinate system, the MGS' "Caves of Maryland" provides approximate locations using a quadrangle system to be employed with the use of 7.5" topographic maps. Neither coordinates nor quadrangular data are posted on this page at present, only surrounding terrain and the condition/accessibility of said caves when known. While limited data and pictures about Maryland's caves can be found on the MGS’s website, the best sources of information are local speleological grottos and knowledgeable enthusiasts. To learn more about the caves of Maryland, their locations, and ethical caving practices in general, contact the Tri-state Grotto, an internal organization of the National Speleological Society.
Maryland geology & caves
Most of Maryland’s caves occur in its three western most counties (Washington, Allegany, and Garrett). While Maryland may be smaller than many of its neighboring states containing larger numbers of caves, its geology likewise allows for the formation of underground cavities, most of which are hollowed out by chemical processes—these caves are known as solutional caves. Non-solutional caves are carved out by weathering and are typically of smaller size and of little interest to spelunkers. Underlying layers of carbonate rocks form much of Maryland’s bedrock; precipitation and groundwater react with such rocks as dolomite, limestone, and marble, dissolving the rock and forming small fissures and chambers that allow for the entry of more water and the dissolution of more of the carbonic rock. Being able to identify the different types of rock that caves are likely to form in can provide a great deal of background into a cave’s likely history, and thus these rock formations will be further discussed moving east to west across the state.
Coastal Plain – this is the area of Maryland extending from just west of the Chesapeake Bay to the Atlantic Ocean: Precambrian rocks are mostly overlain by gravel, silts, marls, and sands, and consequently no solutional caves are known to exist in this region of Maryland.
Piedmont Plateau – an area of gently rolling hills and flatlands, the Piedmont is home to only a few of Maryland’s caves as most of its members are unsuitable for their development or are largely hidden from view beneath surface settlement. Exceptions in the uplands area include the Wakefield and Cockeystown marbles, which are known to include but a few caves. In the lowlands portion of the Piedmont (known as the Frederick Valley) caves are found in the Frederick and Grove Limestones (upper Cambrian and lower Ordovician, respectively); while several other limestone members exist (Tomstown and New Oxford) no caves have been located within these members.
Blue Ridge & the Great Valley – the Blue Ridge rises up from the Piedmont just west of Frederick in the first of its two mountains, Braddock/Catoctin. Here older limestone and dolomites from the Cambrian/Ordovician make an appearance, offering up a few caves in the Frederick/Middletown Valley vicinity. On top of these, older, harder thrust sheets of metamorphic rocks from the Paleozoic give these mountains their well defined crests and ridges. Wolf Rock, home to Maryland’s best-known non-solutional cave, is an example of quartzitethat has endured while Catoctin Mountain has weathered around it.
South Mountain, which serves as a natural border between Frederick and Washington counties, is the western edge of Maryland’s Blue Ridge, giving way to an area of relatively little relief, known as the Great (or locally, Hagerstown/Cumberland) Valley. Here the harder metamorphosed rocks of the Blue Ridge are replaced by carbonates, sandstones, and shale that grow progressively younger moving west, entering the early Ordovician period. The highest concentration of Maryland caves lies within the Hagerstown Valley, where well-established waterways have cut into the underlying carbonate rocks.[3] Recent fieldwork, combined with the observations of Franz and Slifer, indicate that the most cavernous units exposed in the great valley are, from oldest to youngest, the Tomstown Dolomite, the Cavetown member of the Waynesboro Formation, the lower beds of the Elbrook formation, The Rockdale Run Formation, and, especially cavernous, the Chambersburg Formation. The probability of cave development, however, is also very strongly influenced by the presence of structural features such as anticlinal axes, synclinal troughs, and faults. In contrast to the larger caves of neighboring West Virginia, caves in the great valley are generally quite shallow with little internal relief. In-cave relief rarely exceeds 50 feet (15 m) in Washington County. High deformation and faulting allows surface waters to penetrate rock vertically, and reach the shallow underlying water table quickly without much lateral travel. This serves to limit cavern development considerably, and of the many caves in Washington county, only Crystal Grottoes is known to exceed 1,000 feet (300 m) in length, and it attains such length from having a maze pattern of passages, rather than a long continuous stream conduit.
Ridge & Valley Region – is the name of the physiological province extending west of the Great Valley to the western portion of Allegany County. This region is traditionally defined as starting at Fairview Mountain and is characterized by repeating southwest to northeast trending ridges and valleys. A fault just east of Fairview indicates where younger rocks from the Ordovician - Devonian are being subducted by their Cambrian neighbors to the east. The region is built upon shale and sandstone from the upper Ordovician and lower Silurian periods, with little or no cave-bearing limestone seen until the lower Helderberg Formation with its Wills Creek and Tonoloway Formations. Larger members of the upper Devonian consist of the Keyser Limestone and New Creek Limestone, in which some of the largest caves in the state can be found.
Allegany Plateau – the Allegany is a rolling upland punctuated by deep, rounded valleys and ridges of distinct, broad anticlines. Shale andsandstone of the Ordovician and lower Silurian are replaced by limestone formations which continue into the lower Devonian. These younger rocks have settled to a depth equal to that of the much older rocks of the Ordovician; this change in depth occurs along a fault just east ofDan's Mountain. Moving west from outcrops of early Devonian limestone, the Helderberg comes to an end consisting of clastic rocks that bear no caves. Synclines within this region have preserved remains from the younger Carboniferous Period—the period containing Maryland's only natural source of carbon fuels—within the Carboniferous' Mississippian system lies the Greenbrier formation, the next oldest limestone member known to contain caves. The Greenbrier is relatively thin but contains three large caves, including the largest cave in Maryland (Crabtree Cave). The youngest rocks to contain caves are in Garrett County: they are Pennsylvanian in age. All younger sediments have been removed from the landscape with the exception of the Dunkard Group, a small knob in Allegany County that is Permian in age.
List of caves
All caves given in the 1976 republication of Caves of Maryland will be listed below by county. The condition and status of many of these caves are unknown at this time; in an effort to establish an up-to-date record of these caves, editing of the list with any new information is encouraged!
Washington County
Washington County contains roughly sixty percent of all known caves in Maryland. Natural forces have exposed many of the older carbonate rocks underlying the Hagerstown Valley; one such member, the Tomstown Dolomite, found at the western foot of South Mountain, is home to the largest concentration of caves in Maryland, with over 30 known caves. Other areas of notable subterranean activity occur primarily along the county’s well-established stream and creek beds, where incisions into the surrounding rock faces have allowed for increased drainage and erosion. Caves are largely concentrated around these areas of high drainage, specifically the Mount Aetna, Beaver Creek, andAntietam/Little Antietam watersheds, as well as along the massive cliffs adjacent to the Potomac River. Notable members in this region include the Stones River Limestone, Conococheague Limestone, and the Beekmantown, Elbrook, and Tonoloway formations. Washington County is also home to Maryland's only show cave, Crystal Grottoes, which will not be discussed further in this article.
- Action-Hole - (Closed by N.P.S., 11/09)
- Ankeney - several sources indicate the existence of a cave on the west side of "The Neck" south of the Four Locks area; the entrance is said to be small and obscure, the cave containing at least two rooms, though the property owner said it had never been completely explored. This cave was not located during fieldwork in 1969, but would be developed in the Conococheague Limestone at 400' (Lost).
- Antietam - a crawlway over 100 feet (30 m) long was reported to exist in on the east side of a ravine east of the village of Antietam in the Tomstown Dolomite at 380'. The cave could not be located during fieldwork in 1969 and was suspected to be filled or covered; local residents interviewed insisted that this cave connected with an opening in a quarry near Burnside Bridge (almost 2 miles to the north), though this seems highly unlikely; a more likely possibility would be that these reports referred to nearby Marker Cave (Lost, 11/09).
- Antietam Crack - (Open with landowner permission, 8/08)
- Antietam Creek - three small caves can be found along the west bank of the Antietam Creek between Funkstown and Roxbury, all found in the Beekmantown Limestone. Caves #1 & #2 are within relatively close proximity in a section of creek opposite Clagget Mill Lane; Cave #3 has two entrances and is about 2.5 miles south of Cave #2; it can be found at the tip of the meander in the creek east of Roxbury Road.
- Antietam Quarry - a small cave is in the north wall of an old quarry south of Antietam in the vicinity of Limekiln Road; the quarry is in the Tomstown Dolomite and said to overlook the Potomac River, with the two-foot cave entrance 30 feet (9.1 m) above the quarry floor at 400' (Closed by private owner, 11/09).
- Artz - can be found in the tract of Nation Park Service land southeast of McMahon's Mill; the C&O Canal Toepath has been closed in this area due to repeated flooding and erosion, but the cave is said to be at the top of a 40-foot (12 m) cliff overlooking the river (Closed by N.P.S., 11/09).
- Avey Hill - (Open with landowner permission, 11/09)
- Boonsboro Sinks - located on the property of the Boonsboro Livestock Exchange are several sinks discovered when the B.L.E attempted to excavate a pond in the area north of their building. After completion, the pond lost all its water after several weeks, revealing several sinks—some twenty feet deep—in the dry bed. Attempts at digging here yielded little results, but the authors of "Caves of Maryland" felt this area—underlain by the Tomstown Dolomite—had a high probability of containing caves.
- Bowman - the entrance to Bowman Cave, developed in the Tomstown Dolomite at 640', is reported to be tight slit under a low ledge on the property southeast of the LaForge quarry east of MD Route 66 and north of I-70. This tract of land lies on a small hill covered in forest and dense vegetation (could not be located, 3/10).
- Busheys Cavern & Cavetown Quarry Caves - three caves once existed in an old quarry in the Tomstown Dolomite just north of Cavetown. All three caves have been largely destroyed by blasting in the quarry, though the site remains of significant historic importance. Bushey's Cavern was mentioned in journals as early as 1748; in the 19th century the cave was showcased for a small admission fee; by 1925, quarry operations caused the cavern to collapse all-but completely. Two other caves, Busheys Blasted Cave and Busheys Quarryside Cave, as well as the remnants of the cavern, can still be seen in the north part of the quarry today (destroyed, 1925).
- Cave-in-the-Field - found in a prominent sinkhole in a meadow southwest of Downsville and 750 yards north of the McMahon's Mill cave system, the entrance is four feet high and fifteen feet wide, trending down some sixty feet to a cylindrical well; the cave is developed in the Stones River Limestone at 380' (Closed by private owner, 11/09).
- C&O Canal - east of Shepherdstown several old lime kilns exist on a farm; in the hillside beside an old barn are two deep quarries, one of which is filled with water and contains the large, 35-foot-wide (11 m) entrance to the cave, which is a single room extending east for 70 feet (21 m) where it ends in a clay bank. This cave is developed in the Elbrook Limestone close to its contact with the Conococheague Limestone and lies on the southeast flank of a minor anticlinal fold (Closed by private owner, 11/09).
- Column - this cave is the southernmost in a system of closely related caves consisting of King Quarry, Hogmaw, and Column (a fourth, Keedy Cave, may represent a small offshoot of this system). The entrance is 250' south of Hogmaw Cave's entrance, and opens toward the northeast in the base of a former quarry 120' east of the Little Antietam Creek. Column Cave is dry and may represent a now defunct upper level of the much-wetter Hogmaw Cave, which is thought to overlap with Column Cave at its southern extent. The cave is relatively low and contains about 90' of wide passage. Like all the caves in this system, it is developed in the Tomstown Dolomite (Closed by private landowner, 11/09).
- Cool Hollow Well - a low passage in the Elbrook Limestone was discovered at the bottom of a 35-foot-deep (11 m) well in front of the Cool Hollow House along Alternate U.S. Route 40 (unknown).
- Crystal Grottoes - Maryland's only show-cave, developed in the Tomstown Dolomite at 420'.
- Crystal Grotto Quarry - two small caves can be found on the south bank of the stream running from Crystal Grottoes towards Keedysville, adjacent the remnants of an old limestone quarry approximately 300 yards due south-southwest of the neighboring show-cave; both are developed in the Tomstown Dolomite at 420'.
Dam #4 Cave
- Dam #4 Cave – with an easily discerned entrance located shortly after C&O Canal mile marker 83, this cave most often contains an active stream during the wet months that can be circumvented with little difficulty to access the rest of the cave. This cave is roomy enough, with adjoining levels and crossovers; it is in the Conococheague Limestone (Open to visitation)
- Dam #6 Mine - the entrance to this cave, which appears to have natural origins but was expanded as a mine, can be found at the crest of the Tonoloway Ridge, overlooking Great Cacapon across the Potomac River north of Deneen Road; it is developed in the Oriskany Sandstone at 540'.
Rattle Run entering Darby Cave
- Darby - is in a narrow band of Tonoloway Limestone, west of Indian Springs Road and south of Mooresville Road. Over time the waters wore through the limestone here, entering the sub-terrain and leaving behind a dry creek bed to the north where it once held domain. The underground waterway extends for some 120 feet (37 m) where it pools at a deep siphon and disappears. No specific resurgence of the run has been located, but its course is presumed to rejoin with the north branch of the run and the Licking Creek, just a short distance to the north.
- Dargan Mountain
- Dargan Quarry - the quarry is southwest of Dargan along the C&O Canal. Two caves exist in the quarry wall proper: one at the northeast corner, and one another hundred feet south of the first. A large opening 200' south of the quarry is said to be the remnants of a manganese mine and contains two natural cave passages trending north and south. Elevation of said caves is approximately 300'(Open to visitation).
- Dellinger's - a popular cave developed in the Stones River Limestone, the cave contains over 200' of passage. The entrance to this cave is small and faces south, about 100' above the Potomac River at an elevation of 300' (Open to visitation).
- Dog House - a small cave in a hillside near Beaver Creek on the property of the Cushwa Brick Company; the cave trends southwest for twenty feet and is near the contact of the Elbrook Limestone and the Waynesboro Formation at an elevation of 500' (unknown).
- Drain Ditch - cave with one crawlway and room trending northwest once existed in a drainage ditch north of MD Route 34 north of Keedysville; like all caves in this area, it was in the Tomstown Dolomite at an elevation of 390'(Filled).
- Eby - a narrow pit emptying into a crevice that trends northwest is located near Pinesburg; the entrance shaft is said to be in the corner of an open meadow underlain by the Chambersburg Limestone at 470'; the cave is named after the former landowner who at one time resided west of the meadow (unknown).
Thrust sheet of Conococheague Limestone near Fairview
- Fairview Caves – a prominent thrust sheet of limestone can be found along the west bank of Conococheague Creek, near the community of Fairview. Several openings are developed in the face of the rock, including a fissure approximately 3 by 5 feet (0.91 × 1.5 m) tall out of which evidence of a spring can be observed year round. The largest cave in this cluster can be found at the rock’s eastern extent. Here, 100 feet (30 m) of low, dry crawlway eventually leads to a large, muddy interior with high ceilings. These joint controlled passages are home to a few formations and several flowstones, with several intermittent sections of higher and lower passage. Despite its extent, the furthest reaches appeared to have been visited by a raccoon and some inconsiderate party-goers. This was presumed to be Fairview Cave during the Franz/Slifer survey, though some discrepancy exists when compared to the initial report filed by Davies. (Open, but private owner will investigate trespassers, 01/10)
- Fake Fossil - (Open to visitation).
- Flook's Fissure - in 1955 Hurricane Hazel opened a fifteen foot fissure in the Tomstown Dolomite at 440', half a mile north of Snively's Caves; the fissure has since been filled with debris (Filled).
- Gold Mine Cave - local residents report the existence of another cave in the area between Jugtown and Mount Aetna (information pending 3/10).
- Ground Hog - developed in the Tomstown Dolomite at 580 feet (180 m); this small cave contains one triangular shaped room and is located on the ridge east of Bowman's Cave.
- Grove - the entrance is at the mouth of a wooded ravine in an outcropping 25 feet (7.6 m) above the Antietam Creek; it extends northeast for 15 feet (4.6 m) before tapering out. Just north of the cave on the same hillside are several springs; Grove Cave is developed in the Elbrook Limestone at 380 feet (120 m).
- Hepburn - developed in the Tonoloway Limestone at 510 feet (160 m), near a contact with the Wills Creek Shale. The cave is about a mile north of Hancock and is said to drain much of the valley to the west of Cove Ridge. In 1969 the water in this cave was said to be contaminated with organic pollution. The water siphons out of this cave via the floor; a possible resurgence is suspected 3/5ths of a mile southwest of the cave in a large spring that supplies water to Hancock. A lake situated in a line-of-travel connecting the cave and spring has trouble holding water and thus may be linked to the system.
- Hogmaw - the entrance to Hogmaw Cave is on the southeastern face of a sink approximately 550' south of the King Quarry Cave. The cave contains over 250' of wet passage, with water levels varying as much as three feet depending on seasonal rainfall. Hogmaw, King Quarry, Keedy, and Column Caves are all presumed to be of a related system due to their common dip and a shared proximity to the Little Antietam Creek, and are all developed in the Tomstown Dolomite (Closed by private owner, 11/09).
- Holmes - according to the 1976 publication of Caves of Maryland, the entrance to Holmes Cave is .3 miles north of what is now Hagerstown Community College, on the west side of a low ridge. The entrance is two feet square and extends northeast as a dry, dusty crawlway for approximately 30 feet (9.1 m) with one small room that doubles back under the entrance passage. The cave, however, has not been located due to a discrepancy between the publication’s description of the location and the accompanying coordinates. The elevation is said to be at 600 feet (180 m) in the Beekmantown Limestone; the only other topographic clue as to its location is that it is 30 feet (9.1 m) north of a 6-foot-deep (1.8 m) sinkhole containing a small opening (lost, 3/10).
- Houpt - developed in the Elbrook Limestone at 520 feet (160 m); the cave has been closed and the water therein diverted for use at the fish hatchery (Closed by fish hatchery, 11/09).
Howell Cave
- Howell Cave – is located west of McMahon's Mill (not the cave) near mile marker 88; during the wet months entrance to this cave is impeded by a small stream flowing from its low, gravel-lined mouth which sets back in a rocky alcove off the canal; located in the Stones River Limestone (Open to visitation)
Entrance to Jugtown Cave
- Jugtown - can be found north of the Jugtown Road half-way up a wooded hillside. A stream that runs parallel the road is now the principal source of drainage in the area, but at one point water levels were apparently sufficient enough to connect the stream and the cave (which contains its own stream). Following a dry stream bed from the current stream will reveal the cave's entrance, 6 feet (1.8 m) wide by 3 to 5 feet (0.91 to 1.5 m) high, which slopes downward in breakdown to the join the cave's only room. Beyond here the cave extends southeast, towards the mountain, along a narrow stream bed. Jugtown Cave is located in the Tomstown Dolomite at 740 feet (230 m) (open with landowner permission, 11/09).
- Keedy Cave - a small, dry cave in the Tomstown Dolomite, 330' east of Hogmaw Cave; its entrance faces south, and the cave proper contains no more than 25' of passage. This cave is was likely once an offshoot of the King Quarry-Hogmaw-Column Cave system.
- Keedysville Caves - six small caves are located along the Little Antietam Creek's east bank at around 400 feet (120 m), just south of Keedysville. These caves are relatively small and developed along joints striking north; these caves are said to be dead (no confirmation)
- King Quarry - the history of this cave dates back to 1960, when it was exposed by quarrying operations during the construction of MD Route 67. This cave contains two levels and approximately 200' of passage, though reports suggest that still more passage or even a third, lower level may exist to the south, trending off in the direction of Hogmaw Cave. King Quarry cave has suffered damage from blasting during the quarrying operations that opened it, especially near its entrance. Like its neighbors (Hogmaw Cave, Keedy Cave, and Column Cave), King Quarry Cave is developed in the Tomstown Dolomite and is the northern most cave known in the King Quarry-Hogmaw-Column Cave system (Gated).
- Licking Creek - directly under the I-70 bridge where it crosses Licking Creek a cluster of openings can be found; these caves are developed in the Helderberg Limestone, though none can be followed for any great distance due to the narrowing of the passages.
- Limekiln Bend - (Open to visitation).
- Marker - located along Antietam Creek, this cave was once the site of an archeological investigation that produced Native Americanremains.[6] Tradition has it that the cave once served as both a dueling and a burial place. The cave is at the base of a forty-foot cliff (Closed by private owner, 11/09)
- Mega-hole
McMahon's Mill #1
- McMahon's Mill Cave #1 - located on the northeast side of a wooded sink almost directly above Howell Cave; more exploration is needed, as this low cave was largely full of water when explored; located in the Stones River Limestone (open, December 2008) (Open, 12/09)
McMahon's Mill #2
- McMahon's Mill Cave #2 – is located in another sink a short distance northwest of Cave #1. The cave is very fragile and beautiful. For this reason, it is closed by the landowner. (Closed by private owner, 11/09)
McMahon's Mill #3
- McMahon's Mill Cave #3 - The entrance levels are developed along vertical joints in the rock, while a lower level seems to be controlled by the flow of water along the horizontal beds of Stones River Limestone. Equipment recommended/upper-body strength a must for exiting; reports indicate that visitors are unwelcome by the property owner, who would most likely prosecute trespassers. (Closed by private owner, 11/09)
- Mt. Aetna - in August 1931 a cave was discovered in the vicinity of what is now MD Route 66 and Mt. Aetna Road. The following year the cave was opened commercially to the public by unknown parties, but the endeavor failed within six months due to lack of revenues. The property was later sold in the early 1960s; due to increasing vandalism the cave was enclosed by a wooden structure. The cave is on the property of the adjacent quarry, and was gated between 2005 and 2008 by the Tri-state grotto. The cave is developed in the Tomstown Formation at 540 feet (160 m), in particularly dense dolomite, and is rich in formations. The cave is essentially one large passage nearly 400 feet (120 m) long, with one side passage near the entrance (Gated).
- Mt. Aetna Quarry - a cave was once reported to exist in the west waoo of the quarry south of Mt. Aetna Cave along Md Route 66; elevation 540', developed in the Tomstown Dolomite (unknown).
- Natural Well - one and a quarter miles west of Downsville, on the Scott farm, is a sinkhole enclosed in a wooden structure. A stream flows out of a nearby pool, across the sinkhole, and down into a siphon where it disappears. This siphon is thought to be the headwaters responsible for carving out a system of caves to the south, included Cave-in-the-Field, McMahon's Mill Caves, and Howell Cave; like its relatives, the sinkhole is developed in the Stones River Limestone at an elevation of 540' (unknown).
- Neck - 400 yards northwest of the farm at the tip of "the Neck" is a cave developed in nearly vertical beds of the Conococheague Limestone; the entrance is 5'x3' and faces the river, extending some forty feet north where a back entrance allows passage back to the surface. The cave appears to be non-solutional and is likely of tectonic origin, although several sinkholes exist in the bluffs north of Neck Cave, and the property owner indicated the existence of a second cave (Ankeney Cave) which could not be located. Elevation 400' (Open to visitation).
- Pine Hill - two caves were once said to exist in a sloping meadow 300 yards east of the Antietam Creek, due east of Breatheds Station. The caves would have been developed in the Elbrook Limestone at an elevation of about 500', but the entrance shafts were filled with debris in the 1930s and likely remain so today (unknown).
- Pinesburg - located near the top of a cliff along the C&O Canal, the entrance is 3' wide and 6' high, extending north-northeast for about seventy-five feet; the cave is developed in the Stones River Limestone at 500'; a second cave is said to exist in the Pinesburg Quarry, 200 yards west of Pinesburg Station (Open to visitation).
- Red Hill - located south of Keedysville, the entrance is 4'x4' and has remnants of a stone wall on the left side; the cave trends north for 110'. A small sink exists above the cave, which is relatively shallow. The hill acquired its name from the iron-rich sediments beneath it, and the cave was apparently expanded as a result of a minor mining operation prior to the Civil War; it is developed in the Tomstown Dolomite at 420' (Closed by private owner, 11/09).
- Revells - a unique cave on the southern bank of a large oxbow carved out by the Licking Creek in the vicinity of Pectonville. The main passage is at the crest of an anticline, with its subordinate forming a complex lattice of low passages trending to the south. The back-most passage is reported to have once extended some hundreds of feet further through the hill to open out on the other side, though this has not been confirmed. Revells Cave is developed the in thinly-bedded black limestone of the Tonoloway Formation at 450' (Open with landowner permission, 2/09).
- Rohrersville #5 - located in the vicinity of the King Quarry-Hogmaw-Column Cave system, #5 is a small hole on the west side of an outcrop, dropping five feet into a fissure which divides into two crawlways, each extending about twenty feet towards the east. The fissure is developed in the Tomstown Dolomite (condition unknown).
- Round Top Mines - at least eight mines are known to exist in the vicinity of the old cement kiln, below the Western Maryland Railroad near Round Top Hill. These mines are all triangular in shape and likely represent small, natural caves that were enlarged for mining purposes. Mine #1 is 130' east of the mill and 40' of the railroad tracks. Mine #2 is directly north of the mill, 35' above the railroad. Mine #3 is 200' west of the mill and level with the railroad tracks. Mine #4 is the largest, extending over 500' and containing large amounts of water; it is 450' west of the mill and 15' above the railroad. Mine #5 is 1100' west of the mill and just 20' above the C&O Canal towpath. Mine #6 is the best example of what these mines probably looked like prior to being enlarged; it is 20' above the towpath and 800' west of the mill. Mine #7 is 400' west of the mill and 35' above the towpath, and contains remnants of tracks used by mine-carts. Mine #8 is a large (50'x20') shelter cave 900' east of the mill and 25' above the canal.
- Rount Top Summit - one of the largest caves in Washington County, Round Top Summit consist of over 600' of narrow and narrow, fissure-like passage. The cave is also the highest of Washington County caves, developed at 1340' in the knobby-black limestone of the Keyser Formation, and contains several large drops (the largest of which is 40'). The entrance is 5'x3' and opens to the south, while the fissures trend southwest.
- Round Top #2 - during the 1950 expedition, Davies reported the existence of a Round Top Cave #2, which consisted of a straight passage extending some 400'. Repeated efforts were made by subsequent explorers to locate this cave, though nothing was found that matched Davies' description. Two passages were found in the general vicinity on an escarpment: one at the base extending 20', and another 300' east of this passage, extending 60' towards the northeast. These two caves are developed in the Tonoloway Limestone at an elevation around 1100' (unknown).
View of Sepentroph's Hill
- Sepentroph's Cave – can be easily found a short-distance north of Wilson above a watercress field bordering Conococheague Creek. A spring at the base of the road serves as an outlet for water draining from higher elevations; following the presumed path of drainage will reveal the cave's small entrance, half-way up the hillside. This cave can be very constraining, and a large degree of upper body strength is required to exit the cave or reach its upper level after having made the initial drop. This cave is in the Chambersburg Limestone near its contact with the Martinsburg Shale. During the winter months, this cave has been reported to have 'bad air', and so caution is advised. (Open with permission, 11/09)
- Sharman's Run Cave - (Open with landowner permission, 11/09).
- Shockeys Cave - during prohibition a local man named Shockey was said to have run a bootlegging operation out of a small cave northeast of Falls Creek near Fort Ritchie. The cave was said to be in the base of a 40' cliff in Weverton Quartzite; during the survey a local reported that the cave was sealed with rocks years prior (unknown).
- Snively Caves - are located on a broken plateau east of the Little Antietam Creek near Eakle's Mill and south of Dogstreet. There are two main caves and several smaller sinks and ravines of some interest. The caves are near the base of the Tomstown Dolomite at an elevation of 400' (unknown).
- Snyder's Landing Cave #1 – located at the base of the C&O Canal near mile marker 76; located in the Conococheague Limestone (Open to visitation).
- Snyder's Landing Cave #2 – located further downstream from Cave #1; the cave has two narrow entrances along the base of the canal and is in the Conococheague Limestone; easily distinguished from other caves by a third opening located above the right entrance, the two apparently being connected by a chimney (Open to visitation).
- Snyder's Landing #3 - located atop cliff on the margin of a large sinkhole, almost directly above cave #1. (Open to visitation)
"The Face" is surrounded by small caves near Two Locks
- Two Locks - along the C&O Canal between Dam #5 and mile marker 107 are several fissures and suspect openings, almost exclusively surrounding a rocky escarpment of Beakmantown Limestone. The northern most of these caves can be seen as a large fissure on the cliff face looking up-river; at least two other caves exist on the cliff's adjacent face, where footing can be found to access the promotory. Remains at the top indicate this has been a vantage point of strategic importance over the past few centuries, and continues to provide scenic views upriver; remnants of a long-standing outpost or camp, several deep wells and chasms at this site suggest they may connect with the other caves located below the cliff, making this a relatively large system when considered as a whole. (Open to visitation)
- Wheeler Road Crevice - an impressive crevice cave on the eastern flank of a ridge northeast of Keedysville. The fissure is 4' wide and 20' deep, trending northeast for 25' before being reduced to a crawlway that extends for another 20' with several minor side-passages(Closed by private landowner, 07).
Mouth of Wilson Cave
- Wilson - first opened in March 1968, the cave lies in a shallow sinkhole in a wooded area north of the Wilson General Store on U.S. Route 40. The cave is developed in a thin band of Chambersburg Limestone west of Conococheague Creek and east of its contact with the Beekmantown Group, at an elevation of 420 feet (130 m). The entrance is a 12-foot (3.7 m) vertical drop, and a second drop of 35 feet (11 m) must be overcome to gain access to the lower level. The cave is usually wet with a well at the far end that should be considered dangerous to enter. In February 2009, this cave contained very little oxygen, and being difficult to exit, is extremely dangerous. (Open with landowner permission, 01/2010)
- Winder's Cave #1 - is named after a Mr. Winders, who lived off of Crystal Falls Drive, about a mile north of its intersection with Mt. Aetna Road; the land is now maintained by his kin. The caves on his property which is somewhere southwest of Jugtown. Both caves are developed in the Tomstown Dolomite on the east flank of a wooded ridge at around 700 feet (210 m). This cave is said to contain several vertical drops and has two levels, and is likely hydrologically related to Jugtown Cave, one half-mile to the north and slightly to the east. Unfortunately, the Winder family does not want visitors in the cave (due to vandalism); they tell people the cave has been sealed off, but the actual condition is unknown (Closed by private landowner, 12/08)
- Winder's Cave #2 - is located on the same ridge as #1, but hidden somewhere in a small, tree-filled sink 450 yards to the south. The cave is reported to be of relatively little interest, but local reports suggest a third cave may/may have existed in another sink 50 yards to the north (Closed by private landowner, 12/08)
