Newmarket (2008 estimate: 80,400) is a town in Southern Ontario located approximately 45 km (30 miles) north of Toronto, Ontario, Canada. It is part of the Greater Toronto Area and the Golden Horseshoe in an area known as the "905 Region" (a reference to the GTA's telephone area code outside Toronto proper). Newmarket is well connected by highway to the Toronto area, served by three interchanges along Highway 404 and connected to Highway 9. Newmarket is the seat of the County Courthouse of the York Region. Southlake Regional Health Centre (hospital) is located in Newmarket.
The town is bounded on the north by the Town of East Gwillimbury, on the east by the Town of Whitchurch-Stouffville, on the south by the Town of Aurora, and on the west by King Township, themselves all likewise part of York Region.