The Thermal Belt Railway operates from Bostic through Alexander Mills and Forest City to Spindale in Rutherford County , which is located in the foothills of western North Carolina . The company began service in 1990 over former CSX and NS branch lines that were purchased by the Rutherford Railroad Development Corporation, a non-profit community group. The line was subsequently leased to Southeast Shortlines Inc., parent company of the Thermal Belt Railway.