The Claysville "S" Bridge is a historic S bridge in Washington County, Pennsylvania.

The bridge is made of stone and was a part of the Cumberland Road (later National Road) and helped transport wagons and stagecoaches amid the American westward expansion in the early 19th century.

[2] It passes over Buffalo Creek.

[3] In 1947, the Pennsylvania Historical and Museum Commission installed a historical marker noting the historic importance of the bridge.

[2] It is designated as a historic bridge by the Washington County History & Landmarks Foundation.