is a city in DuPage and Kane Counties in the U.S. state of Illinois. The population was 23,866 at the 2000 census. Fermilab is located in Batavia. A 2002 special census put the city's population at 25,246. Batavia is part of a Tri-Cities area, along with St. Charles and Geneva.
Batavia is located at 41°50'48" North, 88°18'30" West (41.846562, -88.308441).
According to the United States Census Bureau, the city has a total area of 9.2 square miles (23.8 km²), of which, 9.1 square miles (23.4 km²) of it is land and 0.1 square miles (0.4 km²) of it (1.52%) is water.