Gimlet Pegram Truss Railroad Bridge, Railroad bridge in Blaine County, Idaho.

The Gimlet Pegram Truss Railroad Bridge is a steel railway crossing in Blaine County that spans the Big Wood River on concrete supports in a single sweep. Its underside displays a distinctive latticed framework structure typical of early 20th-century bridge engineering.

Fabricated in 1894 by the Edge Moor Bridge Works of Wilmington, Delaware, the bridge was disassembled and moved to Blaine County, Idaho, in 1914. It carried Union Pacific trains from 1936 to 1981, bringing skiers to Sun Valley. In 1984 the Blaine County recreation district converted it to pedestrian use, and in 1997 it was listed on the National Register of Historic Places.

From 1936 to 1981 the bridge carried Union Pacific trains bringing skiers to Sun Valley, the resort that opened in 1936 and made this stretch of the Big Wood River a winter-sports destination. The line was known for luxury service to the slopes. Since 1984 the crossing has belonged to walkers rather than trains.

The pedestrian path is easy to navigate, with clear sightlines along the river and surrounding landscape. Better visibility of the structural details occurs during dry weather and daylight hours, making these times ideal for closer inspection.

The bridge's Pegram truss is named after engineer George H. Pegram, but the span itself was fabricated in 1894 by the Edge Moor Bridge Works of Wilmington, Delaware. Look for the riveted latticework of the truss panels, a detail of 19th-century fabrication that predates the bridge's 1914 move to Idaho.