 General Motors traces its roots to the Durant-Dort Carriage Company of Flint named after William C. Durant and Josiah Dallas Dort, and purchased the original Durant-Dort factory (built in 1880 as a woolen mill) on Water Street in May 2013 (and the Durant-Dort office, a National Historic Landmark across the street, as well).The company will take over responsibility for maintenance from the Flint Historical Foundation.On Hamilton Avenue, the oldest buildings opened in 1908.