Southern Arizona Transportation Museum, Transportation museum in downtown Tucson, United States

The Southern Arizona Transportation Museum is a railway and transportation museum in downtown Tucson housed in a restored railroad depot and warehouse building. It displays historic train cars, railway artifacts, steam locomotives, and vehicles from different eras of American transportation history.

The museum occupies the former records vault building of the Southern Pacific Depot, renovated by the City of Tucson in 2004. The depot lobby now serves as an Amtrak waiting room, while other depot buildings are leased to businesses. The museum itself opened to preserve southern Arizona's transportation history.

Each March the museum holds the Silver Spike Festival, marking the arrival of the train in Tucson in March 1880. The 2014 edition drew Mayor Jonathan Rothschild and Arizona Daily Star columnist David Leighton, with a reenactment by descendants of early pioneers Estevan Ochoa, P.R. Tully and Robert Leatherwood, plus music from the 4th United States Cavalry Regiment Band.

The museum occupies the former records vault building at the Southern Pacific Depot, renovated by the City of Tucson in 2004. Admission is free; guided tours cost a small fee and require an appointment. Downtown historic walking tours run October through March. The depot lobby serves as the Amtrak waiting room.

The museum's centrepiece is Southern Pacific locomotive No. 1673, a 2-6-0 M-4b Mogul built by the Schenectady Locomotive Works in New York in November 1900. It is listed on the National Register of Historic Places and stands beside the former Southern Pacific Depot.