Fort Kaministiquia, French colonial fort in Thunder Bay, Canada.

Fort Kaministiquia was a French trading post built at the mouth of the Kaministiquia River in present-day Thunder Bay. The location controlled a crucial route between Lake Superior and the western territories that explorers sought to reach.

French officer Zacharie Robutel de la Nouë founded the fort in 1717 as part of a chain of trading bases. It later became a base for explorer Pierre Gaultier de la Vérendrye's expeditions into western North America.

The name Kaministiquia comes from the river mouth where the fort stood; French spellings varied, from Camanistigoyan to Kaministiquia. Coureurs des bois ranged westward from the post, and their movements were known to the English at Hudson Bay only through rumours. Trade resumed by at least 1767, most likely through the easier Grand Portage route.

The fort site is buried under downtown Thunder Bay, so nothing of the French post is visible. A map drawn in 1802 by British military engineer Ralph Henry Bruyeres shows the location of the French forts; the original sketch is held in the map collection of Library and Archives Canada.

The fort became known more for supporting exploration journeys than for any military function. Its value lay in serving as a supply point and meeting place for traders and explorers heading westward.