Alberta Provincial Highway No. 5, commonly referred to as Highway 5, is a 129-kilometre (80 mi) highway that connects Lethbridge to Waterton Lakes National Park in southern Alberta, Canada. It begins as an east–west highway in Waterton and transitions to a north–south route before ending at Crowsnest Trail (Highway 3) in Lethbridge. Highway 5 is part of the Cowboy Trail between Highway 6 in Waterton Lakes National Park and Cardston.