Collinsville is a city located mainly in Madison County, and partially in St. Clair County, both in Illinois. As of the 2000 census, the city had a population of 24,707. Collinsville is approximately 12 miles from St. Louis, Missouri and is considered part of that city's metropolitan area. Famously, it is the home of the world's largest ketchup bottle, a former water tower, and the world horseradish capital. Collinsville apartments for rent comparison page shows most up to date rent information on Collinsville apartments and houses. Rent information is obtained from multiple rental sources but we cannot guarantee their accuracy.