Ayr, Ontario is on the Nith River in the Township of North Dumfries (2006 pop. 9,063). Shown right is Christ Anglican Church, Ayr established in 1917.
Ayr's earliest industry and settlement, Mudge's Mills, was established in 1824. In 1884, along with Jedburgh (est. 1832 in the east) and Nithvale (est. 1837 in the west) the three settlements were incorporated as the village of Ayr. In 1868, John Watson, a Scottish immigrant, purchased the Abel Mudge property and built the Dam.
In 1865 the John Watson Manufacturing Company (1884) transferred its water rights to the Grand River Conservation Authority and the Village of Ayr, in an overall program of beautification and water conservation. Watson's dam represents one of the important historic features for which the Grand River was designated a Canadian Heritage River in 1994.