Detroit is in the United States.
The Seventeenth United States Census , conducted by the Census Bureau , determined the resident population of the United States to be 150,697,361 , an increase of 14.5 percent over the 131,669,275 persons enumerated during the 1940 Census . The Ambassador Bridge ( officially the Ambassador International Bridge ) is a suspension bridge that connects Detroit , Michigan , United States , with Windsor , Ontario , 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 City of Detroit anchors the second-largest economic region in the Midwest , behind Chicago , and the thirteenth-largest in the United States . Downtown Detroit is the central business district and a residential area of the city of Detroit , Michigan , United States .