Yonge Street is the longest street in the world. It starts from the south of Lake Ontario, goes straight north through downtown Toronto, passing through many towns along the way, then turns west at Cochrane and finally reaches Rainy River with a total length of 1896 kilometers.
Yonge Street divides the whole Toronto into two parts: east and west. Many streets are named "XX Street East" to the east of Yonge Street, and "XX Street West" to the west of Yonge Street. Therefore, even if you haven't been to Toronto, you can sometimes roughly guess the general location of a place :)