Discover Cowles Bog

The lush wetlands and thriving ferns of Cowles Bog form a primeval landscape unlike any other in the Indiana Dunes. A 4.7 mile-trail winds its way beneath the shady branches of black oaks, red maples, birches, tamarack pines, and white cedars. Cowles Bog sits at the foot of a steep sand dune, and the trail climbs dramatically before descending to the shore of Lake Michigan. The beach here is one of the most secluded in the Indiana Dunes, and it offers majestic views of the lake, the city of Chicago, and the mighty steel mills neighboring this natural treasure.

Discovery Trail Logo

Cowles Bog is named for the scientist Henry Chandler Cowles from the University of Chicago. Cowles is one of the founders of the modern science of ecology, and a tireless champion of the dunes in the early twentieth century. Today Cowles Bog is home to over 400 species of plants, and countless varieties of mushroom and fungi. The National Audubon Society designated Cowles Bog an Important Bird Area, and the woods and wetlands here attract a stunning array of birds and waterfowl.

In 1953 Indiana Dunes champion Dorothy Buell and the newly formed Save the Dunes Council purchased the land in hopes it would one day serve as the foundation for a park. In many ways Cowles Bog is the heart of the Indiana Dunes.

The Geological Story of Cowles Bog

Like the rest of the Indiana Dunes, Cowles Bog’s story traces back to the last ice age, when advancing and retreating glaciers carved the landscape and left behind the massive sand dunes and wetlands. In spite of its names, Cowles Bog is scientifically a fen. Bogs, like nearby Pinhook Bog in the Indiana Dunes, are wetlands nourished only by rain or snowfall, resulting in stagnant water that is highly acidic. A fen, on the other hand, is more basic (with a higher pH level) and is fed by fresh groundwater. The combination of the fen, surrounding marsh, and trees makes Cowles Bog what is known as a “swamp complex,” and a vital wildlife habitat.

Aerial view of a water with green and brown vegetation. Trees line the background an a blue sky is above.

Cowles Bog Trail Map

Cowles Bog Trail is an Indiana Dunes National Park classic. The trail highlights the park's outstanding plant diversity, yet it is close to some of Northwest Indiana's industry. Explore several distinct habitats along this 4.7-mile trail, including ponds…

Marvelous Plants of Cowles Bog

A stunning array of plant life thrives at Cowles Bog beneath the branches of the variety of trees growing here. Nestled among the ferns, one can find carnivorous plants like the pitcher plants and sun-dew plants growing in the water. One of the most distinctive inhabitants of the area is the appropriately named skunk cabbage. This amazing plant can trap the heat of the groundwater, allowing it to flower even in colder winter temperatures. Finding pollinators in these conditions can be difficult, and so the skunk cabbage produces an unpleasant odor that attracts flies mistakenly in search of a meal.

Of course, these odiferous plants share space with a number of beautiful and much more pleasant-smelling wildflowers, as well. Native plants like the joe-pye weed and the white astors also flourish in the dunes. Along with milkweed and butterfly weeds, the abundant flowers make Cowles Bog an attractive spot for butterflies.

Visitors to Cowles Bog will immediately notice the waving cattails surrounding the fen. While they may look beautiful, only one species is native, and the other that grows here is invasive. Volunteers and park rangers work tirelessly to remove and control them to preserve this habit for the other species that call Cowles Bog home.

Wildflowers of the Indiana Dunes

The Indiana Dunes is one of the most biodiverse national parks in the entire country. Over 1,100 flowering plant species and ferns make their homes here. How many flowers can YOU find?

Beautiful Birds of Cowles Bog

Like many locations in the Indiana Dunes, Cowles Bog has been designated an Important Bird Area by the Audubon Society. A number of beautiful birds and waterfowl can be found here, including the majestic sandhill crane and the Little Blue Heron. Among the reeds and cattails visitors can spot the American Bittern and marsh wren. The male marsh wren will build multiple nests that they may use throughout the year.

Cowles Bog is also an important habitat for the Virginia Rail, a marshbird considered endangered in the state of Indiana. These birds have a distinctive mating dance, complete with male displays of its wings and mutual bows back and forth.

New to birding?

Grab a copy of this self-led birding tour, and visit six of the Indiana Dunes area birding recommended by local birders. Spectacular birds are waiting for you. Can you spot 'em all?

Cowles Bog Gifts and Souvenirs

Celebrate the birthplace of plant ecology with your very own t-shirt, pajamas, teddy bear, and more. Shop Cowles Bog products in the Indiana Dunes Passport Collection.

Sponsored

Amazing Amphibians at Cowles Bog

The still waters and abundant plant life make Cowles Bog a perfect place for amphibians. The most distinctive resident is the four-toed salamander, which lays its eggs above the water on the thick stalks of grass and cattails. Unlike other salamanders living in Indiana, this is the only species that has just four toes on its back feet.

Noteworthy

A short distance from the trailhead, Cowles Bog trail features a lovely raised boardwalk that allows visitors to walk above this incredible wetland.

In the spring, watch for pairs of Sandhill Cranes raising their newborns in the marsh just off Mineral Springs Road to the east and west.

The northern edge of the trail from the Main Lot takes you by beaver lodges that are right off the trail in the wetland to the south. Watch for them about a mile from the Main Lot.

A sandhill crane looks back at something in the distance. It stands in a marshy area with vegetation.

Get Involved

Be the Change — Volunteer! Get more involved with the Indiana Dunes! There are many no-hassle, drop-in volunteer opportunities available for everyone. Just show up!

Be Responsible

Visitors must stay on designated trails at all times. We have created a video to help you learn about your role in enjoying the dunes area safely while minimizing your impact on the park.

Love & Protect the Dunes

Each of us who visit the Indiana Dunes can also help protect natural heritage, biodiversity, and local culture by taking a few simple steps.

Cowles Bog Trail

1450 N. Mineral Springs Rd.
219-395-1882

This is where Henry Chandler Cowles conducted his landmark study of the dunes’ vegetation succession. You can embark on the 4.5 miles of interconnected trails, choosing a short, moderate hike…

What to Expect

There are two parking lots available at Cowles Bog. For quick access to spring flowers, and ponds filled with Great Blue Herons, Canada Geese, and Capsian Terns, take a left after the railroad tracks on Mineral Springs Road and park in the paved Greenbelt Trailhead lot.

For the fastest route to the boardwalk viewing platform, enter the trailhead through the main parking lot which is located just before the Ogden Dunes town guardhouse.

The trail is a mixture of loose sand and packed dirt with moderate to rugged dune climbs. Visitors will hike along ponds, marshes, and black oak savannas, eventually leading to Lake Michigan.

An aerial view of Cowles Bog

Main Lot (north): 1450 North Mineral Springs Road, Dune Acres, IN 46304

Look for the gravel entrance road on the right just before the town guardhouse.

Free to enter
Open daily from 6:00 am to 11:00 pm
4.7 miles with loops for shorter routes
Not wheelchair accessible
No handicap parking
No drinking fountains
Porta-John available year round

An aerial view of Cowles Bog

Greenbelt Lot (south): 1184 North Mineral Springs Road, Dune Acres, IN 46304

Look for the entrance road on the left just after the railroad tracks.

Free to enter
Open daily from 6:00 am to 11:00 pm
4.7 miles with loops for shorter routes
Not wheelchair accessible
No handicap parking
No drinking fountains
Porta-John available year round

Discover Cowles Bog

The Geological Story of Cowles Bog

Hike the Cowles Bog Trail

Cowles Bog Trail Map

Marvelous Plants of Cowles Bog

Plants You May See

Panicled Aster

Swamp Aster

Red Columbine

Scarlet Strawberry

Moss Flox

Iris Versicolor

Common Lousewort

Boston Fern

Spotted Touch Me Not

Northern White Violet

Star False Solomon's Seal

Wildflowers of the Indiana Dunes

Beautiful Birds of Cowles Bog

Birds You May See

Sandhill Crane

Great Egret

Screech Owl