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When built, this bridge over the Tanana River was among the longest single-span truss bridges in the United States. The 704-footlong, pin-connected, through-truss railroad bridge was designed by Modjeski and Angier of Chicago, consulting engineers. Designed to avoid the necessity for piers in the river, which were subject to damage from ice floes in the spring, the bridge was also elevated to allow river traffic to pass. As a result, the southern approach was extensive, including a 2,880-foot-long timber trestle and a steel viaduct that featured a 120-foot-long Warren deck truss. A steep bluff at the north end of the bridge required only one short approach span. The American Bridge Company fabricated the bridge at its Ambridge works outside of Pittsburgh and transported the bridge parts by rail to Seattle and by boat to Alaska. Construction of the bridge was closely supervised by Col. Frederick Mears, chairman of the Alaska Engineering Commission. He was replaced as chairman in March 1923, three months before the bridge opened, completing the 470-mile length of the Alaska Railroad.