The Friarton Bridge is a lightweight concrete road bridge across the Firth of Tay on the southeastern outskirts of Perth, Scotland, approximately 20 miles upstream of the Tay Road Bridge. The bridge was constructed by the Miller Group and engineered by Andrew Stevenson, and is the first light weight concrete bridge built in Europe, and forms part of the eastern spur of the M90 between junctions 10 (Craigend) and 11 (Broxden), the most northerly motorway junction in the UK. It also forms part of the important east coast road corridor from Edinburgh through to Dundee and Aberdeen. It is the single largest structure on the M90, a title it will hold until the completion of the second Forth Road Bridge in 2016.
It is a two-lane dual carriageway; unusually for a motorway (although not unusually for the M90) neither carriageway has a hard shoulder. When it was built in 1978, it was designated as the M85 motorway. When the A85 from the north end of the bridge to Dundee was renumbered in the early 1990s to A90 through to Dundee, the motorway's designation changed to M90 to provide a continuous route number from Edinburgh through to Fraserburgh.