Capricorn Highway

The Capricorn Highway is located in Central Queensland, Australia, and links the city of Rockhampton with western Queensland. The highway is 575 km long, and joins the Landsborough Highway at Barcaldine. Formerly National Route 66, Queensland began to convert to the alphanumeric system much of Australia had adopted in the early-2000s and is now designated as A4. The highway runs parallel with the Tropic of Capricorn, hence its name.

Other towns situated along the highway include (from east to west): Gracemere, Kabra, Stanwell, Westwood, Gogango, Duaringa, Dingo, Bluff, Blackwater, Comet, Emerald, Bogantungan, Alpha and Jericho.

Running virtually east/west, the highway traverses the area known as the Central Highlands, and crosses the Great Dividing Range between Alpha and Jericho.

State-controlled road
Capricorn Highway is a state-controlled state-strategic road. It is defined in four sections, as follows:
 * Number 16A, Rockhampton to Duaringa.
 * Number 16B, Duaringa to Emerald.
 * Number 16C, Emerald to Alpha.
 * Number 16D, Alpha to Barcaldine.

Northern Australia Roads Program upgrade
The Northern Australia Roads Program announced in 2016 included the following project for the Capricorn Highway.

Highway duplication
The project to duplicate the section between Rockhampton and Gracemere was completed in mid 2021 at a total cost of $75 million. This will facilitate the construction of the south-western entry to the proposed Rockhampton Ring Road.

Northern Australian Beef Roads Upgrade
The Northern Australia Beef Roads Program announced in 2016 included the following project:

Road train access to Rockhampton (stage 2)
The project for upgrading between Gracemere saleyards and the Rockhampton abattoirs to provide access for Type 1 Road Trains was completed by early 2021 at a total cost of $30 million. It involved about 29 km of road improvements on four roads:
 * Capricorn Highway – from Saleyards Road at Gracemere to the Bruce Highway roundabout at Rochhampton (7.7 km).
 * Bruce Highway – from the Capricorn Highway roundabout to the Yaamba Road intersection (8.3 km).
 * Rockhampton–Yeppoon Road – from the Bruce Highway intersection south-west to the Emu Park Road intersection (2.4 km.
 * Rockhampton–Emu Park Road – from the Rockhampton-Yeppoon Road intersection to St Christophers Chapel Road at (10.2 km).

Roads of strategic importance upgrades
The Roads of Strategic Importance initiative, last updated in March 2022, included the following projects for the Capricorn Highway.

Corridor upgrade
A lead project to upgrade the Mount Isa to Rockhampton corridor, including sections of the Capricorn and Landsborough Highways and surrounding state and council roads, at an estimated cost of $237.5 million, was in the planning and scoping stage. Works are expected to include progressive sealing, lane duplications and crossing upgrades.

Intersection upgrade Gregory Highway
A project to upgrade the intersection with the Gregory Highway in at a cost of $7.9 million is scheduled for completion in mid-2023. This project was targeted for "early works" by the Queensland Government.

Intersection upgrade
A project to upgrade an intersection in Blackwater, at a cost of $6.24 million, was expected to finish in early 2022.

Pavement strengthening and/or widening
A project to strengthen and widen pavement just east of Emerald, at a cost of $5 million, was expected to finish in mid-2022.

A project to widen pavement east of Alpha, at a cost of $9.65 million, was due for completion in late 2022.

Intersecting state-controlled roads
In addition to the Bruce, Leichhardt, Gregory and Landsborough Highways, and the Fitzroy Developmental Road, the following state-controlled roads, from east to west, intersect with the Capricorn Highway:
 * Gavial–Gracemere Road
 * Biloela–Duaringa Road
 * Duaringa Connection Road
 * Blackwater–Rolleston Road
 * Blackwater–Cooroorah Road
 * Comet River Road
 * Anakie–Sapphire Road
 * Alpha–Tambo Road
 * Clermont–Alpha Road
 * Blackall–Jericho Road
 * Barcaldine–Aramac Road

Biloela–Duaringa Road
Biloela–Duaringa Road is a state-controlled district road (number 462), rated as a local road of regional significance (LRRS). It runs from the Capricorn Highway in to the Don River crossing on the Gainsford /  boundary, a distance of 24.3 km. It does not intersect with any other state-controlled roads. The physical road continues south as Kokotungo–Don River Road.

Blackwater–Cooroorah Road
Blackwater–Cooroorah Road is a state-controlled district road (number 513), rated as a local road of regional significance (LRRS). It runs from the Capricorn Highway in to the Coronado Curragh Mine in Blackwater, a distance of 15.5 km. It does not intersect with any other state-controlled roads. The physical road continues north.

Comet River Road
Comet River Road is a state-controlled district road (number 4607), rated as a local road of regional significance (LRRS). It runs from the Capricorn Highway in to the northern boundary of, where it becomes Comet–Rolleston Road, a distance of 22.5 km. It does not intersect with any other state-controlled roads.

Anakie–Sapphire Road
Anakie–Sapphire Road is a state-controlled district road (number 5501), rated as a local road of regional significance (LRRS). It runs from Bon Accord Road in, across the Capricorn Highway, to Rubyvale Road in , a distance of 11.1 km. It does not intersect with any other state-controlled roads.

Alpha–Tambo Road
Alpha–Tambo Road is a state-controlled district road (number 443), rated as a local road of regional significance (LRRS). It runs from the Capricorn Highway in to the Dawson Developmental Road in, a distance of 121 km. It does not intersect with any other state-controlled roads.