Castlereagh Highway


The Castlereagh Highway is a state highway located in New South Wales and Queensland, Australia. The highway's northern terminus is at a junction with the Carnarvon Highway, south of, Queensland. Its southern terminus is at a junction with the Great Western Highway at, north of. From north to south the highway traverses South West Queensland and the North West Slopes, Orana, and Central West regions 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.
The Castlereagh Highway was named in 1954 after the Castlereagh River which it parallels for most of its journey north from with the river named in honour of Lord Castlereagh.

Route

The highway was extended past Gilgandra to include state route 86 in October 1997. As such the Castlereagh Highway starts just outside Lithgow at a junction with the Great Western Highway and runs in a north-westerly direction through Ilford and the junctions of Bathurst-Ilford Road and Bylong Valley Way, through the regional centre of Mudgee and Gulgong. From there the Castlereagh Highway is concurrent with the Golden Highway through Dunedoo, then branches off in Dunedoo, continuing past Gilgandra until it reaches the Queensland border via Walgett at Hebel. From there it continues to the outskirts of St George where it terminates with the Carnarvon Highway.
The highway was signed National Route 55 in 1974 north of Gilgandra, and State Route 86 south of Gilgandra. Queensland however signed the Carnarvon Highway as National Route 55 rather than the Castlereagh Highway, causing a major discrepancy for many years in that National Route 55 met the border at Hebel but abruptly begun again over east along the border at Mungindi. The Queensland Road Department changed this and signed National Route 55 over the border north to Charters Towers in later years. This route was soon replaced with the A7 and A55 designations throughout Queensland in 2005, and the B55 designation in NSW during 2013 to Gilgandra and then south to Lithgow, replacing both State Route 86 and National Route 55.

Major junctions