Provincial Trunk Highways (PTH) 100 and 101, collectively known as the Perimeter Highway, form a beltway around the Canadian city of Winnipeg, Manitoba. The Perimeter Highway is approximately 90 km (56 mi) in length and serves as a ring road around Winnipeg for through traffic. It is often considered by local residents to be the city's unofficial boundary, although approximately three-quarters of the Perimeter Highway actually lies in the other municipalities within the Winnipeg Metropolitan Region.