Detroit is in Canada.
Detroit ( [ dᵻˈtrɔɪt ] ) is the most populous city in the U.S. state of Michigan , the largest city on the United States -- Canada border , and the seat of Wayne County . The Detroit Metropolitan Airport is among the most important hubs in the United States . The Michigan Central Railway Tunnel is a railroad tunnel under the Detroit River connecting Detroit , Michigan , in the United States with Windsor , Ontario , in Canada .