Detroit Metropolitan Wayne County Airport is the primary international airport serving Detroit and its surrounding metropolitan area in Michigan, United States. It is located in Romulus, a Detroit suburb. It is by far Michigan's busiest airport, with ten times as many boardings and alightings as the next-busiest, Gerald R. Ford International Airport in Grand Ra…Detroit Metropolitan Wayne County Airport is the primary international airport serving Detroit and its surrounding metropolitan area in Michigan, United States. It is located in Romulus, a Detroit suburb. It is by far Michigan's busiest airport, with ten times as many boardings and alightings as the next-busiest, Gerald R. Ford International Airport in Grand Rapids and more than all other airports in the state combined.