| Unthanks Cave Natural Area Preserve | |
| Iucn Category: | iii |
| Map: | Virginia#USA |
| Location: | Lee County, Virginia |
| Coordinates: | 36.6143°N -83.2267°W |
| Coords Ref: | [1] |
| Area Acre: | 171 |
| Governing Body: | Virginia Department of Conservation and Recreation |
Unthanks Cave Natural Area Preserve is a 171acres Natural Area Preserve in Lee County, Virginia. It protects the entrance to Unthanks Cave, which houses significant biological diversity and a wide variety of invertebrate life. The cave's streams drain a significant karst area south of the Powell River.[2]
A rare species of hydrobiid snail was first discovered in Unthanks Cave in 1986.[3] Holsingeria unthanksensis, also known as the thankless ghostsnail, has since been found in additional cave streams in Lee County, with an additional population noted 500km (300miles) north in Skyline Caverns.[4] Additional unusual species found within the cave include a second hydrobiid snail, the Powell Valley planarian (Sphalloplana consimilis), the Southwest Virginia cave isopod (Caecidotea recurvata), and a cave-dwelling carabid beetle.[5]
The only known entrance to the 7miles cave was purchased by The Nature Conservancy in 1987, and was the first cave system purchased in Virginia by the organization.[6] The Nature Conservancy gave the property to the Virginia Department of Conservation and Recreation in 2004,[2] although they continue to conduct research at the site.[5]
Although previously popular with spelunkers due to the cave's large speleothems,[6] Unthanks Cave is today gated and inaccessible except for official scientific monitoring and inquiry.[2]