South Prairie Hotel in South Prairie, Washington, circa 1900. Frame two-story hotel with large group of children and adults. J.M. Fredrickson collection. Other Subject Classes: hotel, people,

South portal of Great Northern Railway tunnel at Seattle, Washington. South Portal and interlocking. Other subject classes: Tunnel Portal

Soo Line tower at Minot, North Dakota, June 29, 1982. Soo tower at the rail line crossing, photograph by Harold Hall, from the Norm Keyes Collection.

Soo Line Railroad Sheyenne River viaduct looking south bound at Valley City, North Dakota, on May 17, 2003. Photo by GJ Werkema. Other subject classes: bridge, viaduct

Soo Line Railroad Company depot at Cabott, WI, circa 1925. Soo Line depot Cabott, Wisconsin. J.M. Fredrickson collection. Other Subject Classes: depot

Soo Line depot at Paynesville, Minnesota, undated. Soo Line depot, photograph by Jack Porzig, from the Norm Keyes Collection.

Soo Line depot at Omemee, North Dakota, undated. Two story Soo Line depot, photograph by Robert Johnston, from the Norm Keyes Collection.

Soo Line depot at Fairmont, North Dakota, undated. Soo Line depot, photograph by Robert Johnston, from the Norm Keyes Collection.

Smith Tower, Seattle, Washington, circa 1920. Portrait of Smith Tower looking north from roof of a building at 2nd Avenue and Main Street. Photo by Asahel Curtis. Other subject categories: Downtown

Smelter complex at Tacoma/Ruston, Washington, circa 1960. Aerial view of large smelter facility, tall stack, Northern Pacific mainline and Ruston tunnel. Minnesota Historical Society. Photo by J.M. Fredrickson collection. Other Subject Classes: smelter, track, tunnel