Killarney is a municipality located on the northern shore of Georgian Bay in the Sudbury District of Ontario, Canada.

Killarney's established community was founded in 1820 by Étienne De La Morandière (although indigenous peoples were living there prior), a French Canadian originally from Varennes, Quebec and a fur trader in Sault Ste Marie, Michigan, along with his wife Josette Sai Sai Go No Kwe, an indigenous woman from Michigan and a close relative of Chief Kitchi, meaning Big Gun.

Hundreds of people from around Ontario went to Colins Inlet for work and established a large community in the area.

Roy Fruehauf, president of the company from 1949 to 1961, was primarily responsible for operating Killarney Mountain Lodge.

Clients and guests would be flown in via Mallard sea planes for vacations during the warmer summer months.

A quarry in Killarney Bay had fixed this issue for many families by creating more employment opportunities in the area.

The booming tourism industry brought hundreds of thousands of dollars to the businesses of Killarney as well as the many families that contributed to it.

Before that, the people of the town had to either go by boat in the summer to Little Current and then take a train to Sudbury or other areas to obtain food and resources or by horse and buggy in the winter.

In 2006, the municipality was enlarged again (to 1,654.58 km2, 638.84 sq mi) when it annexed the unorganized mainland portion of Manitoulin District.

Despite the municipality's geographic size, most of its population continues to reside in the community of Killarney itself, although smaller settlements also exist at Hartley Bay and Bigwood.

Roque's Marina amenities include camping with 15 or 30 amp power, EV Charge, transient and seasonal dockage, 24hr coin operated laundromat, showers, and indoor toilets, along with block and cube ice.