Cowles Bog

Indiana Dunes and Lake Michigan

4.5 miles loop, 250 feet elevation gain
Difficulty: Easy-moderate
Access: Decent gravel road to trailhead, Indiana Dunes National Park entrance fee required

The Cowles Bog hike allows you to experience a little bit of everything that makes the new Indiana Dunes National Park special: a lush and biodiverse wetland, tall dunes, views of vast Lake Michigan, and reminders of the region's industrial past and present. The bog is named after Henry Cowles, a pioneering ecologist at the University of Chicago who made important observations at this wetland and in the surrounding dunes that contributed to the area's eventual preservation. Although the scenery here is not flashy, I found Cowles Bog to be a joy to hike with its profusion of wildflowers, relative seclusion, and good views. If you have time for just a single hike at Indiana Dunes National Park, Cowles Bog would be a reasonable choice.

I hiked Cowles Bog while visiting Indiana Dunes National Park with a friend living in Chicago. We drove in from Chicago, taking I-94 south and east into Indiana and leaving the interstate at exit 26A for Route 49. Upon exiting, we took Route 49 north for two miles and then made a left turn for the ramp to connect with US Route 12; we took the left fork at the bottom of the ramp to head west on US Route 12. We followed US 12 west for 1.4 miles and then turned right onto Mineral Springs Road. We followed this paved road with no lane divides north for three-quarters of a mile to the gate for Dune Acres; at this point, we turned right and followed a short gravel road into the parking lot for the Cowles Bog Trail. Parking here was somewhat limited, with room for less than 20 cars; if this parking lot is full, you will have to park 2/3 mile to the south at the Calumet Trailhead to access this hike. On a late May weekend day, there was a national park attendant monitoring the parking situation at the trailhead to prevent illegal parking. We were lucky and found a spot, but Indiana Dunes is popular enough that you may need to arrive earlier or later in the day to guarantee finding a spot. There was no entrance fee when I visited, but Indiana Dunes National Park has since implemented entrance fees; I am not certain where fee collection occurs.

From the parking lot, we walked back down the short gravel road to get back to Mineral Springs Road and then crossed the road to reach the start of the trail. The trail started by traveling along an elevated strip between lush, forested wetlands on both sides. In May, the fresh green colors of the forest and bog here were extremely refreshing; this was a landscape bursting with life. Ferns were sprouting up throughout the partially-flooded plane and cattails occurred in open spots with more sun. There was plenty of wildlife as well: we heard the call of birds in the forest and saw a turtle crossing the trail.

Ferns abound in Cowles Bog

The rich vegetation of Cowles Bog

Turtle on the trail

The landscape of Cowles Bog played a crucial role in Dr. Henry Cowles' study of ecological succession. The bog's complex mosaic of habitats, including wetlands, sand dunes, and forests, provided Cowles, then a professor at the University of Chicago, with a unique opportunity to observe and document the changes in plant and animal communities over time. Cowles' research on ecological succession revealed that the bog was not a static environment, but a dynamic system in which different species of plants and animals replaced one another in a predictable sequence.

Cowles observed that the sand dunes at the bog's edge were colonized by pioneering species of grasses, which were gradually replaced by shrubs and trees as the dunes stabilized. Similarly, he noted that the wetlands in the bog were colonized by different species of plants depending on the depth of the water, and that these communities changed over time as the water level fluctuated. 

After a third of mile of hiking from the trailhead, the wetlands to the right of the trail ended and the trail began following the base of a forested dune; the forested part of the bog still lay to the left (south) side of the trail. At 0.8 miles, we came to a junction where the Cowles Bog Trail began its figure eight loop. Here, we took the right fork, which took us uphill and away from the bog as the trail began its first ascent. This short uphill climb brought me up and over a forested dune; while the vegetation on the hill somewhat hid that all the hills here were just dunes, the loose sand underfoot betrayed that we were on one of the park's namesake dunes. Being amongst the dunes didn't mean that we were done with the wetlands, though: after crossing the first dune, the trail returned to the boundaries of an open marsh.

Cowles Bog

In late May, the forest floor on the dunes was awash with wildflower color. Columbine, geraniums, and lupine were among the many flowers in bloom, lining the sandy path up the dunes.

Blooming geraniums

Columbine and lupine

At 1.2 miles, the trail began another climb into the sandy hills, these forested dunes. The ascents here are somewhat more challenging than trails of a similar grade elsewhere due to the looseness of the sand. The trail here was incredibly idyllic, though, because of the flowers dotting the forest floor. The trail came to a junction at 1.4 miles, where the left fork cut the loop short; we took the right fork to proceed along the main Cowles Bog Trail to the shores of Lake Michigan.

Trail across forested and flower-coated dunes

The trail went up and down through this stretch of the Indiana Dunes until, at 1.7 miles, we emerged in the open atop Mount Bentley Dune, adjacent to the lake. From this open vantage point, we enjoyed the best views of the hike, which encompassed the neighboring forest, an expanse of sand beneath my feet, and the placid waters of Lake Michigan ahead.

Mount Bentley dune and Lake Michigan

Gazing across the lake, we caught a sight of the faint Chicago skyline; on a less stormy day, it might be more clear. The distinctive forms of the Willis Tower and the John Hancock Tower were both clearly distinguishable, even from this distance. The distant skyline was the only reminder that Lake Michigan was just a lake and not the vast ocean.

Chicago skyline visible across Lake Michigan

After soaking in the dune-top views, we descended down the steep sides of the dune towards the lakeshore. At the base of the dune, we came to a junction with a trail that led west through the grass towards the return leg of the loop; however, we skipped this junction and decided to follow the path all the way down to the waterfront and the beach along Lake Michigan, which we reached at just under 2 miles from the trailhead.

Looking west, we could see the two massive smokestacks of the Bailly generating station, a large coal-fired power plant that is part of the Port of Indiana industrial zone.

Bailly Generating Station at the Port of Indiana

The Port of Indiana was built into the heart of the Indiana Dunes in the 1960s, creating a massive industrial area and port in what used to be the Central Dunes of the Indiana Dunes. Bethlehem Steel and US Steel lobbied for the Army Corps of Engineers to dredge the lake bottom near Burns Harbor to create a deepwater port for transporting coal and steel; the result was this complex just east of Gary. The construction of the port split the Indiana Dunes in two and destroyed a large swath of the central dunes; this was one of the multiple environmental catastrophes affecting the Indiana Dunes that eventually led to the dunes' preservation and recent establishment as a national park.

Looking east along the lakeshore, we had a view of the forested dunes coming down to the water for miles until reaching the NIPSCO Michigan City power plant in the distance, a coal-fired power plant that sits atop the site of one of the other environmental catastrophes of the Indiana Dunes. The power plant is built on the former site of the Hoosier Slide, once the largest of all the Indiana Dunes, which was completely torn apart and mined for its sand to make millions of Ball Corporation Mason jars.

View along the Indiana Dunes to the Michigan City power plant

Ahead of us lay the vast expanse of Lake Michigan- the largest lake fully within the United States, the second largest of the Great Lakes by volume and the third largest by area, truly an freshwater sea. Three hundred miles of open freshwater separated our position on the southern end of the lake from the north shore on the Upper Peninsula of Michigan.

Lake Michigan

We followed the beach to the west for a fifth of a mile and came to a path leading back up the dunes from the beach at 2.2 miles into the hike. Taking this path, we began the return leg of the loop. After crossing a flat, grass-covered stretch of the dune, the trail embarked on a steep climb up the forested dune of Mount Tuthill. This was the steepest and most extended ascent of the hike: the trail notches 120 feet of elevation gain in one go here. Although potentially tough for Midwest standards, hikers visiting from more mountainous areas are still likely to find this a short uphill climb.

Back among the wooded dunes, we enjoyed the forested landscape and the profusion of spring wildflowers blooming amidst the blooms. The spring scenery here was overwhelmingly verdant. Only the sand underfoot reminded us that these hills were sand and not soil. 

Lupine blooming on the wooded dunes

At 2.7 miles, we passed a junction that headed towards the inbound leg of the loop; we stayed to the right at the junction and continued on the larger loop. This trail briefly followed a low sand ridge before it dropped down to the bog and cut through the wetlands. At times, there were glimpses from the trail to the nearby Port of Indiana complex and its sprawling industrial campus.

Cowles Bog

At 3.3 miles, we came to another trail junction where the Greenbelt Trail split off from the Cowles Bog Trail. The right fork for the Greenbelt Trail followed the southern boundary of the bog to Mineral Springs Road; we took the left fork, which kept us on the north end of the bog. We closed the loop at 3.6 miles into the hike and then followed the path through the bog that we had come in on back to the trailhead.

Overall, I found this to be a very enjoyable and rewarding hike and the highlight of my day in the Indiana Dunes. The diversity of scenery on this hike- sandy dunes, blooming forest, a vast lake, verdant wetlands, industrial history, and a plethora of wildlife and wildflowers- made this a satisfying and unique experience and makes this a highly recommended hike when visiting the Indiana Dunes.