Sydney Orbital Network

The Sydney Orbital Network is a 110 kilometremotorway standard ring road or orbital around the city of Sydney, the capital of New South Wales in Australia. It runs north from Sydney Airport, underneath the CBD to the North Shore, west to the Hills District, south to Prestons and then east to connect with the airport. Much of the road is privately owned and financed by tolls.

Planning for this beltway, orbital or ring road began as early as 1962 under the "County of Cumberland scheme" (CCS) and well talked about as far back as 1944. Then from 1973 to 1989 things started to take shape with new sections opening-up and then further advancing by 1999. In 2007, the Lane Cove Tunnel opened, completing the orbital network.

The 110 km Sydney orbital consists of several motorways and freeways, they are listed below:

The major sunken/underground sections of the orbital are:

The major elevated sections are:

The widest part of the orbital is the Warringah Freeway approach to the Sydney Harbour Bridge, the longest tunnel is the M5 East tunnel, and the largest interchange is the Light Horse Interchange between the M4 and M7, a 4-level stack. It would cost over $30AU to take the whole orbital without exiting once. The average width of the Orbital is 3 lanes in each direction (The M7 and the M5 East are 2 lanes in each direction, the Lane Cove Tunnel is mostly 3 lanes in direction, however the M2, Gore Hill Freeway and M5 are 3 lanes each way while the Warringah Freeway is between 6-8 lanes each way for its short duration of around 3km).

There is significant upgrade work occurring as part of the WestConnex project, which will see the M5 duplicated (total of 4 lanes each way) along with the addition of new freeways to the Sydney network.

The Sydney Orbital Road Network consists of a number of roads built by private companies: tolling is unavoidable when using the road network.

Intercity highways are linked to the Orbital, moving traffic away from the old busy National Routes. They are:

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