British Columbia provincial highway 37, the Cassiar Highway, is the northwesternmost highway in the province, and it is very scenic, passing through some of the most isolated areas of B.C. The highway first gained its '37' designation in 1975, and at that time, its southern terminus was at the community of New Hazelton on the Yellowhead Highway. In 1979, the highway's Yellowhead junction was relocated to a point on Highway 16 just south of the site of Kitwanga. Highway 37 was then extended south to Kitimat in 1986, using a stretch of road that used to hold the designation of Highway 25. There are many sections on Highway 37 north of the Yellowhead that are not paved.

Route details

Highway 37 starts its 874 km journey in the south at Kitimat. 59 km north, Highway 37 reaches Terrace, where it merges onto the Yellowhead Highway. The Yellowhead carries Highway 37 east for 91 km to the Kitwanga Junction, where the Yellowhead diverges east.

North of the Yellowhead's Kitwanga junction, Highway 37 travels 76 km to the community of Cranberry Junction, and then another 80 km north to the Meziadin Junction, where Highway 37A begins. Highway 37 travels north through the Skeena Mountain range for 333 km to the Continental Divide community of Dease Lake. Another 116 km north and Highway 37 reaches Jade City, where a junction to the former Asbestos_mining community of Cassiar is located. North of Jade City, Highway 37 travels another 120 km to its crossing of the 60th parallel into the Yukon Territory, terminating at a junction with the Alaska Highway near Upper Liard just 3 km later.

British Columbia provincial highway 37A, the Stewart Highway, is a 65 km-long spur off of Highway 37 west to the border towns of Stewart and Hyder, where an Alaska Marine Highway terminal is located. Highway 37A was given this designation in 1984.