Theodore Roosevelt Expressway (TRE) is the northern third of the Ports-to-Plains Corridor. It runs from Rapid City, SD to Canada through the Port of Raymond in Montana into Saskatchewan, Canada. The TRE Corridor serves the Bakken Region including the states of North Dakota, South Dakota, Montana and the province of Saskatchewan.

The mission of the Theodore Roosevelt Expressway Association is to assist in “Growing the Great Plains Region with our partner organizations through corridor development, marketing initiatives, and trade promotion opportunities nationally and internationally."