Either side of the Gwydir Highway lie two vastly different ecosystems, separated by only a few metres of tarmac. Washpool Park, with its rich volcanic soil, supports a dense rainforest in a patchwork of different climates, with warm temperate forest interspersed with subtropical and dry forest. It is home to the largest remaining undisturbed warm temperate forest in New South Wales, as well as hosting the world’s largest forest of coachwood trees.Gibraltar Range Park, on the other hand, is a ruggedly dramatic landscape, covered in rocky outcrops, cascading waterfalls and sharp cliffs. The park is distinctly dry in comparison, mostly covered in sub-alpine heathland, and thick forests of drier eucalyptus species.This phenomenon is due to the different kinds of soil in either park, which each support unique plant habitats.
The Gwydir Highway that separates the parks was constructed on a natural division between the two contrasting environments.
Both parks were listed as World Heritage Sites in the late 1980s in order to conserve the rare and endangered species that live there.Washpool was once home to an abundance of valuable red cedar trees, which attracted loggers to the forest.All but two of these giants was cut down in the 20th century, leading to the region being designated a national park in 1979 for the protection of its tree and plant species.The Twin Cedars are thought to be more than 1,000 years old, and are the only two remaining in this part of New South Wales.In spite of protests by locals and restrictions by park authorities, logging continues in Washpool, leaving scars in the forest and reducing the habitat of animal species.Washpool is home to a number of rare animal species, with these threatened mammals, the long-nosed potoroo, the rufous kangaroo rat and the spotted-tailed quoll, calling the park home.