Monticello is a city in located next to the Mississippi River in Wright County, Minnesota, United States. The population was 12,759 at the 2010 census.Monticello is a vibrant small city tucked up against the Mississippi River and conveniently located between St. Cloud and the Twin Cities. This growing community offers an array of business, dining, and retail opportunities as well as a wide variety of recreational activities.Monticello is proud of its extensive parks and pathway system, which includes 28 city owned and maintained parks and miles upon miles of winding trails. Lake Maria State Park, Montissippi Regional Park and the Harry Larsen Memorial Park are three of the largest. At Swan Park, each winter between December and March, as many as 2,700 trumpeter swans nest near Mississippi Drive in Monticello, as the Mississippi River is heated from warm water discharged by the Monticello Nuclear Generating Plant.