Explore Yukon Highways
This map is from a 1972 brochure, "travelling yukon", published by the Yukon Dep't of Travel and Information. The information on the highways reads:
The Nahanni Range Road (Hwy. 10) runs 125 miles from Mile 67 of the Robert Campbell Highway to the Canada Tungsten Mine. It's a summer only road and there are no facilities or services on the road or at the mine site.
See the Robert Campbell Highway page for that information from this brochure.