The Bridge of Forss carries the A836 across the Forss River to the west of Thurso. It is a twin stone arch bridge which appears to date from the early 19th century, and shows some influences from Thomas Telfords work, although it is not believed to have been his work. The bridge was widened on the downstream side, probably in the 1930s, with concrete arches abutting the old work and faced with stonework which had been taken down from the old bridge.
The bridge sits on a sweeping bend on the road as it negotiates the small valley, which means that the road curves as it crosses the bridge. The bridge, however, remains straight, and so at the eastern end the road is pinching the pavement on one side, with a shorter parapet / wing wall. The road then straightens up as it crosses the first arch, before curving in the opposite direction over the western arch, and again pinching the pavement as it begins to curve away once more.
