Detroit () is the most populous city in the U.S. state of Michigan, the fourth-largest city in the Midwest and the largest city on the United States–Canada border. It is the seat of Wayne County, the most populous county in the state. Detroit's metropolitan area, known as Metro Detroit, is home to 5.3 million people, making it the fourteenth-most populous metropolitan area in the United States and the second-largest in the Midwestern United States (behind Chicago). It is a major port on the Detroit River, a strait that connects the Great Lakes system to the Saint Lawrence Seaway. The City of Detroit anchors the second-largest economic region in the Midwest, behind Chicago, and the thirteenth-largest in the United States.