Garratt Road Bridge consists of two adjacent bridges over the Swan River, linking the suburbs of Bayswater and Ascot in Perth, Western Australia. The upstream bridge was built in 1935, while the matching downstream bridge was built in 1972.
The site was significant prior to the construction of Garratt Road Bridge – it featured in Aboriginal mythology, and was in the near vicinity of 1880s bridges for pedestrians and trains. From that time there were various proposal to provide a vehicular crossing between Bayswater and Bassendean. Interest peaked in 1928, but plans were delayed due to the Great Depression. The first bridge, designed by Main Roads Chief Engineer Ernest Godfrey, was constructed in 1934–35. It allowed two lanes of traffic to cross the Swan River, alongside pedestrians on an adjacent footbridge.
Increasing traffic volume led to the bridge being widened by one and a half metres (5 ft) in 1962. By the end of that decade, a second bridge was being planned to cope with rising levels of congestion. It was constructed during 1971–72, but with only a 40-year design life as it was expected to be redundant once the planned Beechboro–Gosnells Highway (modern-day Tonkin Highway) opened. From the 1970s, Main Roads has maintained the bridges with procedures that vastly extended the bridges' lifespans, including concrete overlays on the decks, and retrofitting of steel girders. The heritage value of the structure was recognised in 1998, and Garratt Road Bridge was included in the City of Bayswater's Municipal Heritage Inventory. Eleven years later, in 2009, it was added to the state heritage list, and a permanent entry was given on 23 March 2010.