About This Place
Marengo is a city in McHenry County, Illinois, United States. The population was 6,355 at the 2000 census.
Marengo is located at 42°15′3″N 88°36′18″W / 42.25083°N 88.605°W / 42.25083; -88.605.
According to the United States Census Bureau, the city has a total area of 4.0 square miles (10.3 km²), all of it land.