Complex sentence: Parliament Street was served by the Toronto Transit Commission's Parliament streetcar from 1910 to 1966, which ran from Parliament Loop south of King Street north to Viaduct Loop, near the current site of Castle Frank station.
Split into simpler sentences: Parliament Street was served by the Toronto Transit Commission's Parliament streetcar from 1910 to 1966. It ran from Parliament Loop (south of King Street) north to Viaduct Loop, near the current site of the Castle Frank station.