The A4320 is a short link road to the east of Bristol city centre.
The road starts at the roundabout for the M32J3, which is also the junction for the A4032 and B4052. The dual-carriageway road runs southwards and crosses the A432 at a large traffic-light-controlled junction. The road passes past a number of tower blocks and similar housing, built to replace the properties demolished by the building of the road. The road then comes to the large Lawrence Hill Roundabout junction with the A420 and carries on southwards.
St. Philip's Causeway
The road now crosses the remains of the Midland Railway mainline from Bristol to Birmingham (now a branch to the refuse depot) and passes the Barrow Road industrial estate, with the obligatory traffic-light junction for access to the estate. The road then crosses the modern mainline from Bristol to Birmingham and runs on the three-quarters-of-a-mile-long St. Philip's Causeway, across the mainline to London, the River Avon feeder, and the 4th railway in a mile, the St. Philip's Marsh depot line. The road comes to a roundabout providing access to the Avon Meads retail development and St. Philip's Marsh industrial area, before crossing the main River Avon on a pair of bridges. These bridges are on the site of a former railway bridge for the North Somerset branchline, but both road bridges appear new so the railway bridge was presumably demolished.
After the river is another roundabout providing access several car dealerships and a large supermarket, and the A4320 turns right, curving around to meet the A4 Bath Road at Arno's Vale, at a rather over-complicated set of lanes controlled by traffic lights.
Proposed Bristol Outer Circuit, late 1960s
This road constitutes the only part built of the proposed Bristol Outer Circuit Road. This road was originally envisaged in the Bristol City Development Plan in 1966 and was to run from the end of the M32 through Easton, Totterdown, Bedminster, Clifton, Montpelier and rejoin the M32 at J3.
The first section through Easton, from the M32 to the A420, was built in the early 1970s with the demolition of a huge number of houses. Plans were well advanced to continue the road across St Philip's Marsh and through Totterdown, where another 500 houses were compulsorily purchased and demolished, but no work on the road actually started. With the change of local government in 1974, the plans were put on hold and formally cancelled by the incoming Conservative Government in 1979. The large scar in Totterdown caused by the demolition was left for a number of years before being redeveloped in the late 1980s.
In the late 1980s, a cut-down version of the road was proposed joining the original section at Barrow Road, crossing the railway and river on a large viaduct, and joining the A4 at Arno's Grove. This was built in the early 1990s and opened in October 1994.