Castlereagh Highway

The Castlereagh Highway is a 790-kilometre (490 mi)[1] 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 St George, Queensland. Its southern terminus is at a junction with the Great Western Highway at Marrangaroo, 10 kilometres (6.2 mi) north of Lithgow. From north to south the highway traverses South West Queensland and the North West Slopes, Orana, and Central West regions of New South Wales.

Castlereagh Highway

New South Wales
Walgett Dick O'Brien Bridge.jpg
Dick O'Brien Bridge (1991) carrying Castlereagh Highway over Barwon River, Walgett, NSW.
General information
Length790 km (491 mi)[1]
Route number(s)
route number
Major junctions
North end
South end
Major settlementsDirranbandi, Hebel, Walgett, Gilgandra, Dunedoo, Mudgee, Cullen Bullen
Highway system

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.[2]

The Castlereagh Highway was named in 1954 after the Castlereagh River – which it parallels for most of its journey north from Gilgandra[3] – with the river named in honour of Lord Castlereagh.[4]


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.[5]

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 100 kilometres (62 mi) 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.[3][6]

Major junctionsEdit

StateLGA / LGALocationkm[1]miDestinationsNotes
QueenslandBalonneSt George00.0  Carnarvon Highway (A55) – St George, Surat, Roma
  Carnarvon Highway (46) – Goondiwindi, Mungindi and to Moree
T intersection northern terminus; north (A55) and southeast (46) as the Carnarvon Highway.
Castlereagh Highway continues south as A55.
Dirranbandi6842Noondoo-Mungindi Road - south-east  – MungindiT intersection; Castlereagh Highway continues west
8855Railway Street - west - DirranbandiT intersection; Castlereagh Highway continues south
9056Bollon Dirranbandi Road - west  – BollonT intersection; Castlereagh Highway continues south
Hebel15496William Street - west  – GoodoogaT intersection; Castlereagh Highway continues south
Queensland – New South Wales state border15898Queensland – New South Wales state border  north as A55;
  south as B55
New South WalesWalgettWalgett274170  Gwydir Highway (B76) - north-east  – CollarenebriT intersection; Gwydir Highway south-western terminus; Castlereagh Highway continues south
Barwon River281175Dick O'Brien Bridge
WalgettWalgett284176Kamilaroi Highway (no shield) - east  – NarrabriT intersection; Castlereagh Highway continues south; Kamilaroi Highway continues east
Namoi River288179Bridge over the river (no known name)
WalgettWalgett289180  Kamilaroi Highway (B76) - west  – NarrabriCastlereagh Highway continues south; Kamilaroi Highway continues west; concurrency terminus
Castlereagh River404251Bridge over the river at Coonamble (no known name)
Castlereagh River462287Bridge over the river at Armatree (12 kilometres (7.5 mi) south of Gulargambone) (no known name)
GilgandraGilgandra501311Oxley Highway - west  – Warren, NevertireT intersection; Oxley Highway continues west; Castlereagh Highway continues south
501311  Newell Highway - south-west  – DubboT intersection; Newell Highway continues south and east: Castlereagh Highway continues east
Castlereagh River501311Bridge over the river at Gilgandra (no known name)
GilgandraGilgandra502312  Newell Highway - north-east  – Coonabarabran, Moree to
  Oxley Highway – Gunnedah, Tamworth, Port Macquarie
T intersection; Newell Highway continues north; Castlereagh Highway continues southeast; concurrency terminus
Castlereagh River541336Bridge over the river 12 kilometres (7.5 mi) west of Mendooran (no known name)
WarrumbungleMendooran553344Mendoran Road - north-east  – Binnaway, CoonabarabranT intersection; Castlereagh Highway continues east
Dunedoo591367  Golden Highway - west  – DubboY intersection; Golden Highway continues west
Talbragar River596370Bridge over the river (no known name)
WarrumbungleDunedoo601373  Golden Highway - east  – Merriwa to Singleton, NewcastleT intersection; Castlereagh Highway continues south; Golden Highway continues east; concurrency terminus
Wialdra Creek638396Bridge over the river (no known name)
Cudgegong River657408Holyoake Bridge (1km North of Mudgee)
Mid-WesternIlford725450Bylong Valley Way - east  – Kandos, Rylstone, Bylong, Sandy HollowT intersection; Castlereagh Highway continues south; Bylong Valley Way western terminus
727452Bathurst-Ilford Road - west  – Sofala, BathurstCastlereagh Highway continues south
LithgowMarrangaroo790490  Great Western Highway (A32) – Bathurst, Lithgow, SydneyDirectional T interchange; southern terminus; east and west as the Great Western Highway
1.000 mi = 1.609 km; 1.000 km = 0.621 mi

See alsoEdit


  1. ^ a b c Google (15 November 2017). "Castlereagh Highway" (Map). Google Maps. Google. Retrieved 15 November 2017.
  2. ^ "Welcome to Castlereagh Highway". Lonely Planet. 2016. Archived from the original on 30 October 2016. Retrieved 30 October 2016.
  3. ^ a b "Castlereagh Highway (NSW)". Ozroads. Retrieved 30 October 2016.[self-published source]
  4. ^ "Castlereagh River". Geographical Names Register (GNR) of NSW. Geographical Names Board of New South Wales. Retrieved 18 January 2013.  
  5. ^ "Map of Castlereagh Highway". Bonzle Digital Atlas of Australia. Digital Atlas Pty Limited. 2016. Retrieved 30 October 2016.
  6. ^ "Castlereagh Highway (NSW)". Australian Towns, Cities and Highways. Brisbane, Australia: MG. June 2006. Archived from the original on 10 May 2017. Retrieved 30 October 2016.[self-published source]