Two years later George Ranken, a local magistrate, found fossil bones of both a diprotodon and a giant kangaroo in the caves.

Ranken returned later that year with Sir Thomas Mitchell and collected a huge variety of bones from the caves which appear to have acted as a natural trap for fauna.

Since that time the cave has been a steady source of information about ancient geology and fauna — especially when Gerard Krefft, Curator of the Australian Museum, conducted two separate extensive excavations (in 1866 and 1869) and collected many significant fossil specimens for the museum[2][3] — although collapses and other geological phenomena have splintered and scattered skeletons.

Organised tours of Cathedral Cave began about 1885 with the appointment of the first caretaker, James Sibbald.

The mine passages, mostly backfilled and collapsed, lay dormant for almost 80 years until they were reconstructed and reopened for tours in 1996.

Over many years, members of the Sydney University Speleological Society (SUSS) have mapped extended and discovered new sections of caverns in the area.

in 2019 a new Visitor Experience Centre was constructed to include a Cafe, award winning museum exhibition and discovery classroom running lab sessions for families and children.

McCavity is the under-water section of the cave which was discovered by members of the Sydney University Speleological Society.