Middle Island is a small island, just 18.5 hectares (46 acres) in size. It is the southernmost point of land in Canada, located at 41°41'N, 82°41"W (41.685,-82.684), or about 41.7 degrees north latitude. It lies in Lake Erie, just south of Pelee Island, and is part of Point Pelee National Park. It forms part of the province of Ontario. The southernmost part of the island lies some 150 metres (164 yards) from the U. S. maritime boundary. The distance to the northernmost point of land in Canada—Cape Columbia, Ellesmere Island—is 4,640 kilometres (2,883 miles).
The southernmost point of Middle Island is at a latitude of North 41°40'53", which is slightly lower latitude than the southernmost point in Michigan, and Mentor, Ohio. Twenty-seven U.S. states lie all or partly north of this point, as do European cities such as Rome and Barcelona. Thirteen states are entirely north of this latitude (Alaska, Washington, Oregon, Idaho, Montana, North Dakota, South Dakota, Minnesota, Wisconsin, Michigan, Vermont, New Hampshire, and Maine).
There are no permanent settlements on Middle Island, as the entire island is a conservation area. The most common species are cormorants, though several others also nest there. The birds are so plentiful that in May 2008, Parks Canada attempted to cull the number of cormorants from more than 4000 nests to between 400 and 800. It once was the site of a lighthouse, built in 1872 but which fell into disuse by 1918.
The 15-metre (49 ft) pyramidal square tower burned sometime afterward, but its stone foundation is visible. Located in Canadian waters, and hence indisputably under Canadian sovereignty, the island was privately owned for years by various U.S. owners. Subsequently, Middle Island was purchased in 1999 by the Nature Conservancy of Canada, and then donated to the Canadian national park system on September 6, 2000.