History of Secondary Highway 510:
Secondary Highway 510 is a local highway in the District of Parry Sound that serves as a cut-off route between Highway 520 and Highway 124 north of Magnetawan. Highway 510 was first depicted on a Preliminary Route Plan prepared by the Department of Highways of Ontario (DHO) in April 1956 and was designated by an Order-in-Council dated May 9, 1956. Highway 510 extended north from Highway 520 at Magnetawan for approximately 2 miles (3 km) to join with Highway 124 north of Magnetawan. The highway was already paved at the time of designation in 1956. The route of Highway 510 has not changed since it was first designated. Unless posted otherwise, the speed limit on Highway 510 is 80 km/h (50 mph). Services are not available on Highway 510 itself, but can be found along Highway 520 in Magnetawan.