 Parts of Interstate 85 were already constructed before federal aid was available in the 1950s, as the state had been constructing sections of the Interstate Highway System since 1949.The Lexington Bypass north of Lexington - which at the time was signed U.S. 29 and U.S. 70 - is now a part of Business I-85.This was part of an 80-mile expressway completed in 1955 between Lexington and Hillsborough.