Wilson's Bridge, which is no longer open to vehicular traffic, originally carried the Hagerstown and Conococheague Turnpike, the National Pike, across the Conococheague Creek seven miles west of Hagerstown. The five-arched structure, the longest of the county's stone bridges, is 210' in length and is constructed of coursed local limestone. A tablet set in the north wall of the bridge indicates that the bridge was erected in 1819 by Silas Harry, who had built similar bridges in Pennsylvania. The bridge appears symmetrical with the largest of its five segmental arches being at the center of the structure. The arches are lined with carefully cut voussoirs and are supported by piers terminating with rounded projections. The bridge has received few alterations. changes to the original structure include only some modern repointing, resurfacing of the 19th century road, and replacement of its original wooden coping with concrete. The bridge was bypassed by the present U.S. Route 40 when a newer span was built downstream circa 1935. Wilson's Bridge remained open to traffic until June of 1972 when it was damaged by floods which occurred during Tropical Storm Agnes.
Wilson's Bridge is important for its architecture, its role in commerce and transportation, and its contribution to the knowledge of 19th century engineering. Architecturally the bridge is significant as the oldest and largest of 25 remaining stone arched spans in Washington County. Although it is not the only example of its type, it was the first and served as a pattern for other similar bridges in the area. While stone bridge construction was used elsewhere in the United States, there was a particular concentration of it in Western Maryland and Southern Pennsylvania. Built of limestone, the bridge is enhanced by the fact that the original builder's contract with construction and payment specifications is recorded among the County Land Records. The bridge played an important role in commerce and transportation by aiding travel along the highway linking Western Maryland with Baltimore. Also, it reflects the level of engineering skill at the time it was built. Having carried vehicles for more than 150 years and the heavy traffic of a major road for well over a century, Wilson's Bridge remains as a monument to the engineering capabilities of bridge builder Silas Harry.