Highway 520 begins in Ardbeg as a continuation of the local Clear Lake Road, and travels south then east about 500 metres (1,600 ft) to reach a level crossing of the Canadian National Railway (CN) line at Ardbeg flag stop.

[2] It continues east, then south through a sparsely populated region of the Canadian Shield, though providing access to several First Nation villages.

[3] Southeast of Magnetawan, the highway winds along the northern shore of Cecebe Lake, bisecting several small communities en route.

[3] The portion of Highway 520 from the intersection of Ontario Street south to the Burk's Falls town limits is maintained under a Connecting Link agreement.

[4] Prior to this time, the route was a numbered, but unposted Development Road maintained by the Department of Highways.