CSX Corporation (CSX) is a transportation company. The Company's rail and intermodal businesses provide rail-based transportation services including traditional rail service and the transport of intermodal containers and trailers. CSX's principal operating company, CSX Transportation, Inc. (CSXT), provides an important link to the transportation supply chain through its approximately 21,000 route mile rail network, which serves major population centers in 23 states east of the Mississippi River, the District of Columbia, and the Canadian provinces of Ontario and Quebec. It serves over 70 ocean, river and lake ports along the Atlantic and Gulf Coasts, the Mississippi River, the Great Lakes and the St. Lawrence Seaway. In addition to CSXT, the rail segment includes non-railroad subsidiaries Total Distribution Services, Inc. (TDSI), Transflo Terminal Services, Inc. (Transflo), CSX Technology, Inc. (CSX Technology) and other subsidiaries.