The James Bay Road (French: Route de la Baie James), officially the Route Billy-Diamond Highway, is a remote wilderness highway winding its way through the Canadian Shield in northwestern Quebec and reaches into the James Bay region. It starts in Matagami as an extension of Route 109 and ends at Radisson. The road is fully paved, well maintained, and plowed during the winter. It was originally constructed to carry loads of 300 tons and has mostly gentle curves and hills with wide shoulders.^[1] The road is maintained by the Eeyou Istchee James Bay Regional Government (formerly by the municipality of Baie-James). Connecting to other routes such as the Trans-Taiga Road and the Route du Nord, the highway draws tourists interested in reaching the remote wilderness surrounding James Bay, part of Hudson Bay.

On November 10, 2020, the James Bay Road was renamed in honour of Billy Diamond, former Grand Chief of the Grand Council of the Crees and chief Cree negotiator of the James Bay and Northern Quebec Agreement.^[2]

There is currently^[when?] a proposal supported by the region's Cree communities to build a gravel extension some 250 kilometres (160 mi) farther north to the twin communities on the Great Whale River: the Cree village of Whapmagoostui and the northern (primarily Inuit) village of Kuujjuarapik, in the Nunavik region.

The James Bay Road was conceived as an access road for the hydroelectric projects developed in the James Bay region in the 1970s and onwards. Construction began in 1971 and was completed in October 1974. Gravel branch routes have since been built from the highway, including four roads west to Cree villages on or near James Bay (the one to Chisasibi is paved for most of the way). The Trans-Taiga Road (French: Route Transtaïga) was built and reached Caniapiscau in 1979. The 406 kilometres (252 mi) long Route du Nord (North Road), which also is not a numbered route, connects from km 275 (measured from Matagami) southeast to near Chibougamau, Quebec.

There are no services and development along the James Bay Road except for a full-service station at 381 kilometres (237 mi) from Matagami. The station, located at kilometre marker 381, is operational 24 hours per day, 7 days per week, and is complete with a cafeteria and rudimentary lodging.

Because of the remote nature of the road, there is a registration office along the side of the road for travellers to register. Located a few kilometers north of Matagami, it is staffed 24 hours per day, 7 days per week, and also serves as a tourist office for the communities along or off the James Bay Road.

As further safety provisions, there are six roadside emergency telephones, which connect with staff in the registration office.

• The James Bay Road Check Point
• Distances to each town, from the Check Point.
• S.O.S. phone stations along the James Bay Road
• James Bay Road fuel station
• Road hazard

• List of Quebec provincial highways