Thornhill has a very ethnically diverse population. It is particularly known for its large Jewish community: approximately 40% of the population are Jewish, including many Israeli and Russian immigrants. This community comprises the majority of Thornhill-Vaughan and nearly a quarter of Thornhill-Markham. It is home to one of the largest Orthodox Synagogues in North America.

Located on Toronto's northern border, Thornhill is divided in half between the Town of Markham and the City of Vaughan, and runs along both the east and the west sides of Yonge Street. Today Thornhill has become a bedroom community for those working in the Greater Toronto Area

Thornhill's growth since the 1960s and 1970s has been largely connected to its location bordering what is now the City of Toronto, Thornhill is considered one of the Greater Toronto Area's more upscale communities.

Woodbridge, Ontario is a large suburban community with a population of just over 100,000 just North of Toronto. Its original downtown area is on Woodbridge Avenue north of Highway 7 between Islington Avenue and Kipling Avenue . It was once an independent town before being amalgamated with nearby communities to form the city in 1971.

Although Woodbridge is part of the City of Vaughan, it is still a and well recognized distinct community that is part of the Greater Toronto Area.

Well-known residents of Woodbridge have included:
Elizabeth Arden, (founder of cosmetics company),
Andrew Cogliano (Hockey Player Edmonton Oilers),
Steve Eminger (Hockey Player Washington Capitals),
Kamila Miller (Canadian Idol),
Anthony Nigro (St. Louis Blues org.