Romulus is a suburban city of Metro Detroit, located in Wayne County in the U.S. state of Michigan. The population was 23,989 at the 2010 census, an increase from 22,979 in 2000, making the city the 80th largest city in Michigan. Romulus is home to Detroit Metropolitan Wayne County Airport and a General Motors plant (Romulus Engine) that opened in 1976. The city is the westernmost community in the Downriver area in Wayne County.