Located in Carlyle Lake.

Boulder Campground is situated on the eastern shore of Carlyle Lake, a prime getaway for city-dwellers and families. Located 50 miles east of St. Louis, the area offers the peaceful retreat of a small town combined with the grandeur of Illinois' largest manmade lake.

Boulder Campground offers 82 campsites, all of which have a view of the lake with some sites being perched directly on the shoreline. Each campsite is equipped with electric hookups and provides a picnic area with picnic table and fire pit. The campground has modern amenities such as flush toilets, showers, laundry facilities and drinking water. It is adjacent to the Boulder Day Use Area which provides a boat ramp and fish cleaning station, as well as a reservable group picnic shelter.

Created in 1967, the 26,000-acre lake is recognized as one of the nation's top ten inland sailing lakes and hosts several annual races and regattas.

Carlyle Lake is home to an array of wildlife that can be seen throughout the year. Its waters and shores are a resting spot for migratory waterfowl and other birds. There are six established Watchable Wildlife Sites with viewing towers open to the public around the lake.

The Carlyle Lake Visitor Center, located in the Dam West Recreation Area, has information available as well as nature exhibits on display, including a 215-gallon aquarium with native fish.

Boulder Campground provides fun both on the water and on shore. Boat ramps and courtesy docks are provided, and the vast lake allows for plenty of water sports. Fishing is a popular pastime, and the lake offers year-round varieties of fish such as bluegill, crappie, channel catfish, flathead catfish, white bass, largemouth bass, freshwater drum, carp and walleye. There is an on-site playground and plenty of open space for children to play, as well as an amphitheater for educational programs. A multi-use biking and walking trail is located a short drive away at the dam.