This park boasts a magnificent miscellany of features including 400-million-year-old limestone caves, Indigenous rock art, eerie outcrops and the ruins of Chillagoe's old smelters. The park is spread across the Chillagoe area, with five main signposted access points. Three of the 500-odd caves can be visited on ranger-guided tours: Donna (9am, one hour), Trezkinn (11am, 45 minutes) and Royal Arch (1.30pm, 1½ hours). Donna and Trezkinn require moderate fitness; Royal Arch is easier. Book tickets at the Hub.
There are several other caves you can explore sans-guide, including the deep, dark Pompeii Cave, home to freaky formations and roosting bats. None of the caves are equipped for visitors with disabilities.