Madison County Illinois is located northeast of Downtown St. Louis with the Mississippi River forming its western border. It was formed in 1812 and is 741 square miles. In 2010, the US Census put the population of the county at 269,282. The county seat for Madison County is Edwardsville Illinois.
Madison County has over 40 cities, villages and unincorporated communities. Below is a list of the larger communities that are found in Madison County. Click on any of the links to find that community's specific government information such as the address to the city hall, phone numbers of the mayor, city clerk, police department and other information.