Mears Memorial Bridge, Railway bridge in Nenana, United States.

Mears Memorial Bridge is a railway bridge that spans the Tanana River using a steel Pennsylvania through-truss design. The structure carries a single track and links the northern and southern sections of Alaska by rail.

The bridge was completed in 1923 as the final missing link in Alaska's first transcontinental rail line. A U.S. president traveled to the region personally to celebrate the completion of the rail network.

The bridge is named for Colonel Frederick Mears, chairman and chief engineer of the Alaska Engineering Commission, the body that built and first operated the railroad. The commission's line became today's Alaska Railroad, and the span keeps his name as the railroad's memorial to him.

The bridge is part of an active rail line, so pedestrian access is limited and requires special permission. It is important to check train schedules before visiting the area.

The 700-foot span was the longest simple truss in the United States when built, and it remains the longest span of any kind in Alaska. Its central truss rests on concrete piers about 18 m tall; the southern piers are pile-founded in clay, while the northern pier sits directly on mica schist.