About This Place
Waterloo is a town in Grant and Smithfield townships, DeKalb County, Indiana, United States. The population was 2,242 at the 2010 census.
Waterloo is located at 41°25′53″N 85°1′21″W / 41.43139°N 85.0225°W / 41.43139; -85.0225.
According to the United States Census Bureau, the town has a total area of 1.5 square miles (3.9 km²), all of it land.