The talus caves of the Park were formed when steep, narrow canyons filled with a jumbled mass of boulders from the cliffs above. The canyons are the result of faults and fractures in the central area of volcanic rock.

What is talus cave?

Talus caves are openings formed between boulders piled up on mountain slopes. Most of them are very small both in length and in cross section.

How are caves formed?

Caves are formed by the dissolution of limestone. Rainwater picks up carbon dioxide from the air and as it percolates through the soil, which turns into a weak acid. This slowly dissolves out the limestone along the joints, bedding planes and fractures, some of which become enlarged enough to form caves.