|Area Land||67.07 km2 (25.90 sq mi)|
|Elevation||90 m (300 ft)|
|Postal code||L1S, L1T, L1Z|
|Area code(s)||905, 289, 365|
Ajax is a town in the Durham Region of Southern Ontario, Canada, located in the eastern part of the Greater Toronto Area.
The town is named for HMS Ajax, a Royal Navy cruiser that served in World War II. It is approximately 25 kilometres east of Toronto on the shores of Lake Ontario and is bordered by the City of Pickering to the west and north, and the Town of Whitby to the east.
Before the Second World War, the territory in which Ajax is situated was a rural part of the township of Pickering. The town itself was first established in 1941 when a Defence Industries Limited (D.I.L.) shell plant was constructed and a townsite grew around the plant. By 1945 the plant had filled 40 million shells; employed over 9,000 people at peak production; boasted of its own water and sewage treatment plants.