Southeast Wisconsin is hiding the biggest freshwater cattail marsh in the world

Where America’s biggest cattail marsh lives

You don’t expect a wetland the size of a small city in southeast Wisconsin, but that’s what waits for you at Horicon Marsh.

It spreads across more than 33,000 acres, one of the largest freshwater marshes in the country and, by most accounts, the biggest freshwater cattail marsh anywhere.

The Rock River feeds it before rolling on toward the Mississippi. What you find out here, all at once, is hard to believe until you stand at the edge of it.

From plow and ditch back to water

Settlers once dammed this place, dredged it, and drained it dry to plant crops. For a while the marsh nearly vanished.

Then local conservationists spent decades fighting to bring the water back, and the work paid off. Wisconsin set aside the southern part as a state wildlife area in 1927.

The northern part became a national wildlife refuge in 1941.

Today the marsh carries a title most people never hear, a Wetland of International Importance, and you’d never guess it once grew corn.

Two agencies share one wetland

The marsh splits into two halves that work as one.

Up north, the U.S. Fish and Wildlife Service runs the Horicon National Wildlife Refuge, which covers about 22,000 acres, roughly two-thirds of the whole thing.

Down south, Wisconsin manages the remaining 11,000 acres as a state wildlife area. The two agencies work side by side to keep the water healthy and the birds coming.

Both halves stay open to you all year, so you never have to wait for a season to visit.

Step onto the floating Egret Trail

The Egret Trail puts you right in the middle of the wetland on a boardwalk that floats over the water. It runs as a short, easy loop with flat, level footing, so you can bring just about anyone along.

You stay dry while marsh birds work the cattails an arm’s length away.

Red-winged blackbirds call from the reeds, swallows cut low over the surface, and waterfowl paddle past close enough to count their feathers.

The boardwalk welcomes you year-round, no matter the weather.

See the marsh from your car seat

If you’d rather take it slow, the paved auto tour lets you watch the marsh without leaving your car.

The loop runs about three miles off State Highway 49 and opens to vehicles in mid-March, then closes again in late November.

When it’s open, the road makes a fine ride on a bike too, with a spur that ties into the Wild Goose State Trail. Roll your windows down, drive slow, and let the birds come to you instead of the other way around.

Spring fills the sky with wings

From about mid-April through the end of May, the sky over Horicon goes wild. Hundreds of thousands of ducks pour through on their way north, mallards and teal among them.

Tens of thousands of Canada geese and sandhill cranes drop in to rest and feed. You might catch a white pelican or an egret, birds you don’t expect this far inland.

And under all those wings, frogs strike up a chorus that fills the spring air long after the sun drops.

The fall goose show people drive for

Fall is the season Horicon built its name on. The marsh sits along the Mississippi Flyway, a kind of bird highway that funnels Canada geese, ducks, and sandhill cranes straight overhead.

Historic fall counts have climbed into the hundreds of thousands of geese in a single season. Evenings put on the best show, when flock after flock glides in to roost for the night.

Plan your trip for mid-October through mid-November, and you’ll hit the spectacle near its peak.

More than 300 kinds of birds

Few places stack up this many birds in one spot. More than 300 species use the marsh, and it holds the largest nesting group of redhead ducks east of the Mississippi.

American white pelicans nest on islands tucked deep in the water where you’ll rarely set foot. Along the open channels, you can spot bald eagles overhead and great blue herons standing still as fence posts.

The whole place earned the title of Globally Important Bird Area, and one look up tells you why.

Looking for the rare whooping crane

Among all those birds, one stands out as a true long shot.

The whooping crane ranks among the rarest birds in North America, with only a small number left anywhere in the world. Horicon Marsh gives you one of the better chances to spot one.

Watch for a tall white bird towering over the grayer sandhill cranes around it, and you’ve likely found your prize. Guided crane walks on the boardwalk help you learn what to look for while you scan the water.

The muskrats run the place

Birds get the attention, but plenty more lives out here.

Muskrats swim the channels and pile cattails into little huts you’ll see scattered across the marsh. As they work, they carve open channels of water that help ducks feed and move around.

River otters, red foxes, and coyotes share the same ground.

On warm days, painted turtles line up on logs to soak in the sun, while frogs, dragonflies, and fish fill in the rest of this busy wetland world.

Trails that work in every season

Between the refuge and the state area, you’ve got many miles of trail to pick from. Paths thread through forest, prairie, and wetland, so the scenery shifts as you walk.

One short habitat hike posts signs along the way that explain the local wildlife, handy if you’re bringing kids or just want to learn as you go.

Come winter, those same trails turn into routes for snowshoeing and cross-country skiing. Bring the dog too, as long as you keep yours leashed on most paths.

Three front doors to the marsh

You’ve got three visitor centers to help you find your footing before you head out. The federal refuge visitor center sits off County Road Z and orients you to the northern half.

The state Education and Visitor Center houses the Explorium exhibits, a good stop if you want the hands-on version. The Marsh Haven Nature Center, run by a nonprofit, rounds out the trio.

Each one gives you exhibits, viewing spots, and a way to read the marsh before you walk into it.

Plan Your Visit to Horicon Marsh, Wisconsin

You’ll find Horicon Marsh in Dodge and Fond du Lac counties in southeast Wisconsin, about an hour from Milwaukee and roughly 2.5 hours from Chicago.

It stays open daily, year-round, though the auto tour only runs mid-March to late November while the boardwalk and most trails stay open every season.

Start at one of the three visitor centers to get your bearings, then walk the Egret Trail floating boardwalk and drive the Highway 49 auto tour for your best first look. Check the official website before you go.

This article was created with AI assistance and human editing.

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