Castlereagh Highway

Castlereagh Highway is a 790-kilometre (490 mi) state highway located in New South Wales and Queensland, Australia. From north to south the highway traverses South West Queensland and the North West Slopes, Orana, and Central Westregions of New South Wales.

The highway is part of the Great Inland Way linking Sydney and Cairns, and provides all-weather access to rugged black opal country of Lightning Ridge.

Castlereagh Highway was named after the Castlereagh River, which it parallels for most of its journey north from Gilgandra.