The Boulder Day Use Area is located at Carlyle Lake near Carlyle, Illinois. If you and your family are in search of fun, look no further! Whether you are land loving or ready to venture out on the open water, at Carlyle Lake, there is something for everyone! You can visit for the day or pack up for a longer stay in one of the many lakeside campgrounds and enjoy being surrounded by outdoor adventures. Carlyle Lake offers many opportunities for family fun. From boating and sailing on the open waters, to the sandy beaches and shaded picnic areas, we are sure that you will find plenty of things to do. While here, visitors enjoy a leisurely stroll across the Main Dam; cycle around the lake, or a strenuous workout along the miles of Hiking trails. Each year the Corps of Engineers, along with its partners, Sponsors many special events. Carlyle lake is also known for excellent fishing and hunting areas.