History of Secondary Highway 575 (#1):
The first Secondary Highway 575 was a local highway in the District of Cochrane that provided access from Highway 101 to Night Hawk Lake, located east of Timmins. Highway 575 was first designated by an Order-in-Council dated May 9, 1956. The route, which had been known previously as the Peninsula Road, was first depicted on a Preliminary Route Plan prepared by the Department of Highways of Ontario (DHO) in June, 1956. The highway was gravel-surfaced at the time of designation in 1956, and remained so until the route was re-designated as a Tertiary Highway in the early 1970s. The route of Highway 575 was formally re-designated as Highway 803 by an Order-in-Council, effective July 2, 1970. A different, unrelated Highway 575 has existed in the Sudbury area since 1974.