Australian Speleological Federation (ASF 1985) lists some 37 entrances in the reserve with the Willi Willi Bat Cave being the main feature. This cave is basically one large chamber with a number of branching tunnels connected to it and is used as a maternity cave by bats.
The reserve also contains approximately 2ha of dry lowland rainforest. Much of the dry rainforest occurs on limestone and represents one of the few occurrences of rainforest on limestone in NSW. The rainforest contains a small population of the small-leafed laurel (Cryptocarya williwilliana), a rare endemic to the Macleay Valley.
