The highway officially opened to traffic in 1984 and was assigned the number 77 in 1986. It begins at a point on the Alaska Highway 28 km (17 mi) northwest of Fort Nelson and runs 138 km (86 mi) northeast through expanses of forest to the border of British Columbia and the Northwest Territories, beyond which it continues for 254 km (158 mi) as a very rough packed dirt and gravel road, designated Highway 7. It terminates at a junction with Highway 1 south of Fort Simpson.
In 2012 Peter’s Bros. Construction Ltd. was awarded a contract valued at $8,911,212.00 to pave (level course and overlay) over the existing sealcoat from the end of the existing pavement at km 83 (mi 51.6) to the Northwest Territories border at km 137 (mi 85.1) . The project was completed August 2012.