Route 450 begins in Corner Brook at an interchange with Route 1 (Trans-Canada Highway, Exit 4), with the road continuing northeast as Massey Drive to the town of the same name. It heads west along the southern edge of the city to have an intersection with Wheelers Road, which provides access to the Grenfell Campus. The highway now heads northwest through neighbourhood/industrial area to have intersections with Mac Donald Brown Drive, Lundrigan Drive, Sunnyslope Drive, O'Connell Drive, before making a sharp left turn at an intersection with Route 450A (Lewin Parkway). Route 450 now passes through the Curling section of town before leaving Corner Brook before winding its along the southern shore of Humber Arm to pass through Mount Moriah (where it crosses Cooks Brook), Humber Arm South (where a couple of turns are needed to stay on the highway, one to the right, and the other to the left), and York Harbour, all within the rugged terrain of the Lewis Hills portion of the Long Range Mountains. The highway now enters Lark Harbour and passes by Blow Me Down Provincial Park before passing through town, where it has an intersection with a local road leading to Bottle Cove and Little Port, before the pavement (and Route 450) comes to an end at the eastern edge of town.