The Regional Municipality of Durham (/ˈdʊərəm/), informally referred to as Durham Region, is a regional municipality in Southern Ontario, Canada. Located east of Toronto and the Regional Municipality of York, Durham forms the east-end of the Greater Toronto Area and part of the Golden Horseshoe region. It has an area of approximately 2,500 km2 (970 sq mi). The regional government is headquartered in Whitby.