 About half a mile west of the eastern terminus at SR-204 (Wall Ave), as it starts to pass over railroad tracks, the route splits into a one-way pair, with the eastbound lanes continuing as 21st street, and the westbound lanes located one block to the north as 20th Street.The route was established in 1935.Prior to 1969, the western terminus was the same, but the road followed a slightly more southern alignment along Wilson Lane and about to the east, the route turned southeast (now Exchange Road) and ended at 24th Street (then SR-37, now SR-53) just west of its viaduct.