The Lake County Forest Preserves is a government agency headquartered in Libertyville, Illinois, United States. As principal guardian of Lake County’s open space and natural areas since 1958, it sets the standard in nature and historic preservation, and in outdoor recreation and education.^[1] The guiding elements of its mission remain focused on preservation, restoration, education and recreation. Acknowledged as a regional and national leader, it is the second largest forest preserve district in Illinois.^[2]

In 1958, Ethel Untermyer moved from Chicago to Lake County and looked for a forest preserve near her as her son wanted to go exploring. She was shocked to learn there were none. The next day, she began organizing a countywide referendum to start the Lake County Forest Preserve District. On election day in November 1958, the referendum passed with more than 60% of voter support.^[3] An advisory committee of citizens was formed, with Ethel as its chair.

The Forest Preserves now manages and protects more than 31,200 acres (126.2 km2) of natural lands and more than 200 miles (322 km) of multiuse trails.^[4] Ethel’s Woods Forest Preserve in Antioch, Illinois is named in honor of her efforts to establish the Lake County Forest Preserves.^[5]

In 1961 the first forest preserve opened in Lake County; Van Patten Woods in Wadsworth, Illinois.

A 19-member elected Board of Commissioners governs the Forest Preserves.^[6] They guide the agency's mission and approve all land acquisitions, restoration and improvement projects, educational and cultural programs, the annual budget and other administrative actions. These same officials also serve as County Board members, overseeing all other aspects of Lake County government.

The Forest Preserves manages three public golf courses. Each offers a unique experience, catering to all skill levels while maintaining valuable natural habitats. ThunderHawk Golf Club in Beach Park, Illinois, a top-ranked 228-acre course designed by American golf course architect Robert Trent Jones Jr., features wetlands, oak groves and an elegant clubhouse. Countryside Golf Club in Mundelein, Illinois offers two 18-hole courses. The Prairie Course has wide-open fairways, while the Traditional Course features narrow, tree-lined passages. The facility includes a driving range, clubhouse and PGA lessons. Brae Loch Golf Club in Grayslake, Illinois is a relaxed, scenic 70-acre course with rolling terrain, ideal for beginners.^[7]

The Forest Preserves is committed to sustainable building practices with a focus on net-zero energy. The Ryerson Education Center in Riverwoods, Illinois is a 2,900-square-foot net-zero energy facility that includes two classrooms, extra storage space and a screened porch. It features a 23.8-kilowatt rooftop solar panel system, efficient HVAC, upgraded insulation and windows, LED lighting and bird-friendly glass. It is the first new net-zero energy public building in Lake County to receive certification from the Passive House Institute US (Phius). Other facilities also emphasize energy efficiency. The Operations and Public Safety Facility in Lake Villa, Illinois exceeded lighting and envelope standards with efficient fixtures, daylighting and occupancy sensors. The Ryerson Welcome Center in Riverwoods, Illinois is Platinum LEED Certified and benefits from green infrastructure, a geoexchange system and a solar panel array funded by a local grant.^[8]