The Dallas North Tollway (DNT, or simply the Tollway) is a 30.2-mile (49 km) controlled-access toll road operated by the North Texas Tollway Authority (NTTA), which runs from Interstate 35E near downtown Dallas, Texas (USA), to U.S. Highway 380, in Frisco, Texas. North of I-635, the Dallas North Tollway is accompanied by frontage roads, which are designated as Dallas Parkway for address purposes. This is attributed to when Dallas Parkway was a major thoroughfare before being converted to the current Tollway configuration.