19808 West Grand Avenue
Lake Villa,IL 60046
626 acres
6:30 am–sunset, daily.

Fourth Lake

Named for the lake it borders, the preserve features a scenic peninsula with exceptional lake views, three ponds, a large natural wetland, a fen, and an expansive grove of pines and spruces. A thick group of mature oaks overlooks the lake and surrounding marsh. Due to its nature preserve status, fishing is not permitted at Fourth Lake.


The preserve offers a short 0.3-mile grass loop trail with a scenic overlook near the lake. In addition, a 2.7-mile gravel section of the Millennium Trail stretches through Fourth Lake from just north of Rollins Road to Sand Lake Road where it connects to the existing trail at Bonner Farm and McDonald Woods in Lindenhurst. Please keep dogs leashed and on trails at all times, and pick up after them. Learn about our Off-Leash Dog Areas (permit required).

The site is also home to our Operations and Public Safety Facility, which provides preserve parking and trail access on the north side of Grand Avenue just west of Route 45 in Lake Villa.



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More About This Preserve

The Natural Scene

Fourth Lake and its fen ecosystem are home to a variety of state threatened and endangered plant species and could provide habitat for the American bittern and various rails.

Fens are rare, often sloping, wetlands that occur where mineral rich alkaline groundwater comes to the surface. Unlike bogs, fens have higher nutrient and mineral levels and sustain a more diverse plant and animal community. Fens are often covered by grasses, sedges, reeds and wildflowers.

Considered a swale, rather than a kettle ecosystem, the fen is situated between two ridges of the Valparaiso Moraine. The fen drains south into Fourth Lake, which drains eastward via Mill Creek to the Des Plaines River.


Fourth Lake is listed on the Natural Areas Inventory, which identifies high-quality natural areas statewide. Some of the land here was donated, and the rest was acquired beginning in 1983.

Originally slated as out lots for the Venetian Village subdivision, the land was considered unsuitable for building because of the site's wetland. In addition, a wide drainage ditch ran through the middle of the land.


Preserve parking and trail access available at our Operations and Public Safety Facility on north side of Grand Avenue just west of Route 45.

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