History of Secondary Highway 580:
Secondary Highway 580 is a local highway in the District of Thunder Bay that provides access from Highway 11 near Beardmore to the eastern shore of Lake Nipigon. The proposed route of Highway 580 was first depicted on a Preliminary Route Plan prepared by the Department of Highways of Ontario (DHO) in May, 1956. The highway was designated by an Order-in-Council dated May 9, 1956. Initially, the highway was only paved from the Highway 11 Junction to Leitch Mine, with the balance of the highway having an unimproved dirt surface. The unpaved section of Highway 580 from Leitch Mine to Lake Nipigon was paved in 1961. Unless posted otherwise, the speed limit on Highway 580 is 80 km/h (50 mph). There are no services available on this highway.