Marengo is a town in Liberty Township, Crawford County, Indiana, United States.

One of the tourist attractions and sources of revenue for the town is Marengo Cave, a U.S. National Landmark.

Marengo was originally called Big Springs, and under the latter name was platted in 1839.

[5] Marengo was devastated by an F3 tornado in 2004, resulting in damage to nearly 75 percent of the town and the death of one resident.

According to the 2010 census, Marengo has a total area of 0.77 square miles (1.99 km2), all land.

36.7% of all households were made up of individuals, and 15.6% had someone living alone who was 65 years of age or older.

35.0% of all households were made up of individuals, and 17.9% had someone living alone who was 65 years of age or older.