Area less than one acre Built by Federal Bridge Co. Address Adair, IA 50002, USA Architectural style Arch bridge | Built 1923-1924 NRHP Reference # 98000775 Added to NRHP 25 June 1998 | |
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MPS Highway Bridges of Iowa MPS Architect Iowa Department of Transportation | ||
The Adair Viaduct is a historic structure located in Adair, Iowa, United States. It spans the Iowa Interstate Railroad tracks for 192 feet (59 m). In 1908 Adair County built the first bridge at this location over the Chicago, Rock Island and Pacific Railroad tracks near the site of the 1873 Jesse James train robbery. Increased traffic by the 1920s necessitated its replacement. The Iowa State Highway Commission designed the three-span open spandrel arch bridge. The Adair County Board of Supervisors awarded the $42,263 to build the bridge to the Federal Bridge Company of Des Moines. It is somewhat unique in Iowa in that the bridge is not symmetrical. Because it is located over a deep cut the two approach spans at 56 feet (17 m) each are shorter than the main span, which is 80 feet (24 m). The bridge was opened to traffic in June 1924. It was listed on the National Register of Historic Places in 1998.