Buchanan is a city in Berrien County in the U.S. state of Michigan. The population was 4,456 at the 2010 census. The city is located at the southeast corner of Buchanan Township, about 5 miles (8 km) west of Niles.
According to the United States Census Bureau, the city has a total area of 2.57 square miles (6.66 km2), of which 2.50 square miles (6.47 km2) is land and 0.07 square miles (0.18 km2) is water. (Source, Wikipedia)