Places We Protect

Midewin National Tallgrass Prairie


Closeup view of a Henslow's sparrow perched on prairie grasses.
Henslow's sparrow Henslow's sparrow (Ammodramus henslowii) photographed at The Nature Conservancy's Caveny Tract along the Central Platte River. © Chris Helzer/The Nature Conservancy

Songs from over one hundred bird species can be heard across Midewin’s approximately 20,000 acres of tallgrass prairie.



Please note: For updates on Midewin’s hours and accessibility, please visit the U.S. Forest Service website.

The Midewin National Tallgrass Prairie was established in 1996 on the former Joliet Arsenal. It is the first national tallgrass prairie in the country. Midewin represents a major effort to restore approximately 20,000 acres of farm and industrial land to a unique American landscape and the complex ecology of the prairie. This also makes Midewin the largest open space in the Chicago metropolitan area and northeastern Illinois and the largest tallgrass prairie restoration effort east of the Mississippi River.

Public access to Midewin was restricted during the Army’s cleanup of contaminants remaining from decades of munitions manufacture, but today, 33 miles of trails are open to the public for non-motorized recreation. Midewin will remain a “prairie under construction” for many years to come, so there are many accomplishments for visitors to witness and even help achieve. In 2015, bison were reintroduced at the preserve. 



Visitors can explore 33 miles of trails at Midewin.


Welcome Center hours are 8:00 a.m. to 4:30 p.m., Monday-Saturday from May through October. It is closed on Saturdays from November through April. Trails are open year-round from 4am to 10pm.


There are designated areas for various activities such as biking, hiking, dog walking and horseback riding. Midewin recommends a fat-tire bike for the crushed limestone or gravel trails. Hiking trails are either mowed grass or mulched.


Approximately 20,000 acres

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Photos from Midewin

At approximately 20,000 acres, Midewin boasts hundreds of bird species and rare native wildflowers throughout the preserve.

Entrance sign for Midewin National Tallgrass Prairie.
Three adults standing in a wildflower-covered field under a blue sky to bird watch.
An eastern meadowlark bird sitting on a tree branch.
Wildflowers in a prairie with volunteers in the backdrop.
A black-necked stilt bird stands with its beak in water.
A pale purple coneflower sits in a grassy field surrounded by other flowers.
A trail lined by tall grasses.
A TNC staff member harvesting seed in a prairie.
A loggerhead shrike bird standing on a tree branch.
A butterfly sitting on a wildflower in a prairie.

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Why TNC Selected This Site

The Nature Conservancy has a strong partnership with the U.S. Forest Service to mobilize Forest Service volunteers to support habitat restoration, ecological monitoring, and the Mighty Acorns youth program at Midewin.

Drummond Dolomite Prairie, located on the northwestern corner of Midewin, is some of the most ecologically important land in Illinois. Thin soils over dolomite, magnesium-rich bedrock create a mixture of wet, mesic and dry prairie that supports a wide range of species. Vast open areas provide a haven for sensitive grassland bird species. Midewin’s sheer size provides the opportunity to foster a variety of habitats required by sensitive or endangered species.




    Several threatened and endangered plants are currently being monitored at Midewin, such as leafy prairie clover, glade quillwort, globe mallow, ear-leaf foxglove, Pitcher’s stitchwort and white ladies slipper. Some of these sensitive plants grow within Midewin’s restricted areas.

    Visitors can walk through the 500-acre South Patrol Road prairie restoration, where nearly 200 different species have been planted. Visitors may also enjoy the restored Prairie Creek Woods and see woodland wildflowers such as Virginia bluebells, toothworth, trillium, woodland blue phlox and two orchid species.

    Midewin produces about 30% - 60% of its own native seed at the River Road Seedbeds and Chicago Road Seedbeds, which are both open for the public to visit.


    More than 100 bird species nest and breed at Midewin, and an additional 68 species use Midewin during migration, or as their winter range. Birds that can be seen and heard at Midewin include: threatened Henslow’s sparrows and loggerhead shrikes, endangered upland sandpipers, and more commonly the bobolinks, eastern meadowlarks and dickcissels. More information on these birds along with others that can be spotted at the prairie is available in the Birds of Midewin National Tallgrass Prairie booklet created by our Illinois Chapter and the Illinois Audubon Society. In 2015, bison were reintroduced at the preserve as well.

  • Permitted recreational activities at Midewin include:

    • Hiking
    • Bike riding
    • Horseback riding
    • Dog walking
    • Hunting
    • Volunteering
    • Picnicking
    • Bird watching
    • Tours

    TNC suggests wearing long pants, sturdy shoes and sun protection for hiking. There is no water available at the trail heads. There are designated areas for various activities such as biking, hiking, dog walking and horseback riding. Midewin recommends a fat-tire bike for the crushed limestone or gravel trails. Hiking trails are either mowed grass or mulched.

    The use of Other Power Driven Mobility Devices (OPDMD)s (utility vehicles, ATVs, Segways, golf carts, etc.) on this property has been assessed in accordance with the Americans With Disabilities Act (ADA) regulations. OPDMDs are prohibited.

  • Check out our Illinois Volunteer page to see what volunteer events are available across the state.

    Visit the Midewin volunteer web page to learn more about Midewin volunteer opportunities and submit an online volunteer application. Please contact Volunteer Coordinator Kathryn Gorman at or 815.423.2148 with any questions.

    Visit the main Midewin web site to learn more about Midewin, events, self-guided tours, trails, and hunting guidelines.


The Midewin National Tallgrass Prairie was established through the Illinois Land Conservation Act of 1995. Two years later, the Army transferred the first 15,080 acres of former arsenal lands to the U.S. Forest Service. Later transfers and acquisitions brought Midewin to its current size of 18,500 acres, with an ultimate goal of approximately 20,000 acres.

As the Army completes additional environmental cleanup, more former arsenal lands will be transferred. The Nature Conservancy has been a strong supporter and partner throughout this entire process. TNC has helped support shrike research, deer surveys and bird monitoring and helps manage the award-winning volunteer program at Midewin. TNC is proud to be one of many partners that collaborate with the U.S. Forest Service to manage the largest tallgrass prairie restoration effort east of the Mississippi River.

Find More Places We Protect

The Nature Conservancy owns nearly 1,500 preserves covering more than 2.5 million acres across all 50 states. These lands protect wildlife and natural systems, serve as living laboratories for innovative science and connect people to the natural world.

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