The main area code, 416, was one of the 86 original area codes introduced in 1947. It originally covered most of the populous Golden Horseshoe region in southern Ontario, from Colborne to Niagara Falls to Kitchener-Waterloo.riginal Toronto numbers migrated from six-digit (2L+4N) or manual exchanges include: 1  416-363, 364, 366, 368 (EMpire 3,4,6,8) were originally ADelaide, ELgin, PLaza and WAverly in the Adelaide St (Queen West) area west of downtown. 2  These were the first to be lengthened to 2L+5N in 1951-1953.