Grandfey Viaduct, Railway bridge in Granges-Paccot, Switzerland.

The Grandfey Viaduct is a 343-metre-long railway bridge over the Saane valley at Grandfey, about three kilometres north of Fribourg station. Its present form dates from 1925–1927: six riveted iron lattice piers, encased in concrete, carry five central concrete arches of 42 metres span, topped by arcades that hold the double-track railway bed. A pedestrian passage runs between the central beams.

The original structure was built between 1857 and 1862, using metal trusses on stone pillars to establish a railway connection between the two cities. This construction marked a key milestone in the region's railway development.

The viaduct crosses the Sarine valley at the Röstigraben, the boundary between French-speaking Romandie and German-speaking Switzerland. Since 1988 the passage beneath the tracks has held Richard Serra's steel sculpture Maillart Bridge extended, named after Robert Maillart, the consulting engineer of the 1925–1927 rebuild. Serra's two L-shaped beams frame the crossing like a clamp between the two language regions.

You can walk across the bridge and enjoy views of the Saane Valley, especially from the side areas. Visit on a clear day when visibility is best and the pathways are easiest to navigate.

The lower sections of the viaduct columns have been partially submerged in water since the Schiffenen dam was built in 1964. This unusual feature shows how the landscape changed after flooding without affecting the bridge's function.