The Soo Line Railroad is the primary United States railroad subsidiary of the Canadian Pacific Railway , one of seven U.S. Class I railroads, controlled through the Soo Line Corporation. Although it is named for the Minneapolis, St. Paul and Sault Ste. Marie Railroad (MStP&SSM), which was commonly known as the Soo Line after the phonetic spelling of Sault, it was formed in 1961 by the consolidation of that company with two other CP subsidiaries: The Duluth, South Shore and Atlantic Railway, and the Wisconsin Central Railway. It is also the successor to other Class I railroads, including the Minneapolis, Northfield and Southern Railway (acquired 1982) and the Chicago, Milwaukee, St. Paul and Pacific Railroad (Milwaukee Road, acquired at bankruptcy in 1985). On the other hand, a large amount of mileage was spun off in 1987 to Wisconsin Central Ltd., now part of the Canadian National Railway. The Soo Line Railroad and the Delaware and Hudson Railway, CP's other major subsidiary (before the 2008 DM&E acquisition), presently do business as the Canadian Pacific Railway. Most equipment has been repainted into the CP scheme, but the U.S. Surface Transportation Board groups all of CP's U.S. subsidiaries under the Soo Line name for reporting purposes. The Minneapolis headquarters are located in the Canadian Pacific Plaza building, having moved from the nearby Soo Line Building. System description The company's main line begins at Portal, North Dakota, on the Canada–U.S. border, and extends southeast along former MStP&SSM trackage to the Twin Cities (Minneapolis–Saint Paul). Ex-Milwaukee Road trackage takes the Soo Line from the Twin Cities to Chicago via Milwaukee. Between Chicago and Detroit, where the CP-owned Detroit River Tunnel connects back into Canada, the Soo Line has trackage rights over the Norfolk Southern Railway and haulage rights over CSX Transportation. Major branches include a connection from the border at Noyes, Minnesota, to Glenwood and, until it was sold to the Indiana Rail Road in 1983, a line from Chicago to Louisville, Kentucky. Through trackage rights over the BNSF Railway, the Soo Line also serves Duluth from the Twin Cities. At the end of 1970, the Soo Line operated of road on of track; that year it reported 8,249 million ton-miles of revenue freight and no passengers. History The present Soo Line Railroad was incorporated in Minnesota on October 19, 1949, as the Duluth, South Shore and Atlantic Railroad, as part of the plan for