Riversleigh, in the north-west of Queensland, is Australia's most famous fossil site. The 100 km area has fossil remains of ancient mammals, birds and reptiles of Oligocene and Miocene age.

The fossils at Riversleigh are rare because they are found in soft freshwater limestone which has not been compressed. This means the animal remains retain their three-dimensional structure. The area is located within the catchment of the Gregory River.