South Fork Bridge, Historic bridge in Fountain Lake, Arkansas.

South Fork Bridge is a two-span concrete closed-spandrel arch bridge over the South Fork Saline River in Fountain Lake, Arkansas. Each of its two spans measures 57 feet (17 m), and the roadway is 16 feet (4.9 m) wide. It formerly carried Arkansas Highway 128; its replacement stands just to the south.

The South Fork Bridge was built in 1928 by a county crew, replacing a crossing damaged when major flooding hit the area in 1927. It carried Arkansas Highway 128 until a modern bridge was built just to the south. In 1990 it was listed on the National Register of Historic Places.

The bridge carried Arkansas Highway 128 until a modern replacement was built just to its south, near the junction with Highway 5. Its name comes from the South Fork Saline River it crosses at Fountain Lake. The 1928 county-built arches are visible from the newer road.

The historic structure sits beside a modern bridge that now handles traffic, making it easy to view from nearby. You can approach it directly from the newer roadway without crossing busy traffic.

It earned recognition in 1990 as a historic site and forms part of a larger collection of important bridges from this region. This official designation acknowledges its value as an example of early concrete construction.