At only 100m, Regional Road 581 is the shortest regional road in the Niagara Region.
Regional Road 581, despite its number, no longer connects to Regional Road 81. Regional Road 81 was downloaded through the downtown core in 2002. The majority of Regional Road 581 which used to follow the entire lengths of King and Church Streets was also downloaded to the region at that time. Only the small portion between Niagara Street (Regional Road 48) and Geneva Street (Regional Road 46) remains. A small portion of King Street that was formerly 581 has now been re-designated Regional Road 681.