Thirty thousand islands give Huron the longest Great Lakes shore
Lake Huron, shared by Ontario and Michigan, covers about 23,000 square miles—second among the Great Lakes by area and third among Earth’s freshwater lakes. Count its 30,000 islands and no sibling matches its shoreline length.
Hydrologically it is the eastern half of Lake Michigan–Huron, locked at the same elevation through the five-mile, 120-foot-deep Straits of Mackinac, so the pair forms the planet’s largest freshwater surface. Alone, Huron sits 577 feet above sea level, averages about 195 feet deep, and plunges to 750 feet. Length runs 206 miles with a 183-mile maximum breadth. French voyageurs named it for the Indigenous people they called Huron. Early French visitors nicknamed it the freshwater sea, and a 1656 map by Nicolas Sanson labelled it Karegnondi, a Wyandot word.
Sarnia is the largest city on its shores, with Bay City, Port Huron and Alpena on the Michigan side and towns such as Owen Sound and Collingwood around Georgian Bay. Levels crest in October–November; summer 1986 set a then-record 5.92 feet above datum, and winter 1964 sank 1.38 feet below. Since 2010 the Karegnondi Water Authority has run a pipeline carrying lake water to Flint, Michigan.
Glacial retreat over buried Laurentian valleys left the basin and the submerged Alpena-Amberley Ridge. That ridge runs from Alpena to Point Clark in Ontario, and about 9,000 years ago, with the lake some 100 metres lower, it stood dry and caribou herds crossed it. Divers have found at least 60 stone structures along it since 2008, probably hunting blinds, and in 2013 obsidian from Oregon, proof of trade almost ten millennia old. Before Europeans arrived, a town near the lake held over a hundred large buildings and between 4,000 and 6,000 people.
More than a thousand shipwrecks lie on the bottom, including 212 in Georgian Bay, 185 in Saginaw Bay and 116 inside the Thunder Bay sanctuary created in 2000. The storm of 9 November 1913 raged for 16 hours, sinking 10 ships and killing 235 sailors, and La Salle’s Le Griffon vanished in 1679 after leaving these waters laden with furs.
Source: Lake Huron
