St. Clair Avenue is a major east-west street in Toronto, Ontario, Canada. It was laid out in the late 18th century by the British as a concession road (the Third Concession), 2 kilometres (1.2 mi) north of Bloor Street and 4 kilometres (2.5 mi) north of Queen Street. St. Clair Avenue West has heavy automotive and public transit traffic. Over half the commuters in rush hour traffic travel by the 512 St. Clair streetcar line which connects with St. Clair subway station on Line 1 Yonge–University and St. Clair West station also on the Line 1 Yonge-University subway.