Illinois, Indiana and Ohio share one road, one river, and 300 million years of rock

It’s America’s longest river drive

The Ohio River Scenic Byway runs 940 miles along the north bank of the Ohio River, crossing through Illinois, Indiana and Ohio without ever straying far from the water.

You follow the shoreline past limestone bluffs, thick forest, old farmland and small downtowns that grew up where flatboats once docked.

The road is one of the longest scenic drives in the country, and for long stretches, the river stays right beside you. What lines the banks keeps changing with every state you cross.

Flatboats and frontier towns shaped this valley

Native peoples traveled this valley for thousands of years before European settlers arrived. Ancient earthworks and mounds still stand along the route, built long before anyone put a road here.

Rivermen later turned the Ohio into a busy highway west, pushing flatboats and steamboats downstream to new territory.

The frontier settlements that sprouted along the banks grew into the small river towns you drive through today. Three states share the same waterway, and the byway ties them all together on one road.

Sandstone towers rise from the Shawnee forest floor

Garden of the Gods sits in the Shawnee National Forest in southern Illinois, where sandstone formations took more than 300 million years to carve.

Camel Rock is the one you see on every postcard, but Anvil Rock and Devil’s Smokestack stand just as tall nearby.

A short quarter-mile observation trail loops past the main formations, and you can walk the whole thing in under 20 minutes. The views from up top stretch across forested hills and deep valleys below.

Walk straight into a cavern on the riverbank

Cave-in-Rock State Park sits along the Ohio River in Hardin County, Illinois, and the park takes its name from a wide limestone cavern cut into the riverside bluff.

You can walk right into the cave mouth without a guide or a flashlight. The opening is big enough that you see daylight the whole time.

Trails climb to bluff-top overlooks where the river spreads out below you, and boat ramps at the bottom give direct access to the water.

Small towns with big history line the Illinois shore

Golconda’s downtown still holds rows of preserved historic buildings from the 19th century. Down the river, Elizabethtown sits right at the water’s edge.

Fort Massac State Park in Metropolis holds the title of Illinois’s first state park, and the Shawnee Hills around it earn the whole area its “Illinois Ozarks” nickname.

If you want to stretch your legs between towns, Pounds Hollow and Rim Rock give you forest trails and swimming close to the road.

Four waterfalls crash through deep Indiana gorges

Clifty Falls State Park sits just outside Madison, Indiana, on high bluffs above the river. Four waterfalls cut through the park, and the tallest, Clifty Falls, drops roughly 60 feet into a rocky gorge.

Little Clifty, Hoffman and Tunnel Falls round out the group.

Deep gorges and sheer rock walls surround you on the trails, which range from a paved accessible path to short, steep climbs loaded with stairs.

Overlook Drive takes you to sweeping views straight down into the canyon.

Walk 133 blocks of 19th-century architecture in Madison

Madison’s downtown is a National Historic Landmark District that stretches about 133 blocks.

Federal-style and Greek Revival buildings line the streets, and most of the old storefronts now hold antique shops, galleries and cafes.

You can spend a full afternoon just walking block to block without retracing your steps. Down at the river, Riverfront Park gives you gazebos and brick walkways along the water.

The whole district sits on a bluff, so the views come with the history.

Go underground in Indiana’s cool limestone caves

Marengo Cave has welcomed visitors since 1883, and guided tours still wind past underground rooms packed with rock formations.

Indiana Caverns runs through one of the Midwest’s longest cave systems, carved into the region’s unglaciated hills over millions of years.

Both caves stay cool year-round, so they draw crowds when the summer heat settles in above ground.

You walk through narrow passages one minute and open chambers the next, and the temperature barely changes the whole time.

Stand on 390-million-year-old fossils at the river’s edge

Falls of the Ohio State Park in Clarksville, Indiana, sits on exposed fossil beds that date back about 390 million years.

A shallow sea once covered this ground, and the creatures that lived in it left their shapes pressed into the rock. You can walk right out onto the beds when the water is low.

Inside, an interpretive center explains the geology and river history, and a full-size mammoth skeleton anchors the exhibits. The scale of the fossil beds catches most people off guard.

A Mississippian village still stands near Evansville

Angel Mounds State Historic Site near Evansville, Indiana, is one of the best-preserved prehistoric Native American sites in the country.

A Mississippian community lived here from about A.D. 1000 to 1450, and the earthen mounds they built still rise above the river.

A reconstructed village shows what daily life looked like, with interpretive trails winding across the grounds. You walk the same land where a thriving community farmed and traded for more than four centuries.

Ohio’s first settlement still thrives on the Muskingum

Marietta holds the distinction of Ohio’s first permanent settlement, and the walkable downtown packs in museums and antique shops block after block.

The Campus Martius Museum tells the story of the Northwest Territory right where it started. Boats still moor along the Muskingum River under an antique railroad bridge.

Downstream, Gallipolis sits along a riverside park, founded by French settlers centuries ago.

From Marietta, a Covered Bridge Scenic Byway side trip follows State Route 26 past historic spans, including the 1879 Hune Bridge over the Little Muskingum River.

The world’s largest serpent effigy coils across an Ohio bluff

Serpent Mound winds across a bluff near Peebles, Ohio, stretching about 1,348 feet from its coiling tail to its open-jawed head.

Native peoples shaped it from clay, ash and stone at least 900 years ago, and it remains the largest serpent effigy in the world.

You can walk paved paths that trace the full length of the snake across a grassy plateau, but the best view comes from the observation tower, where the entire form takes shape below you.

A seasonal museum displays ancient tools and interpretive exhibits nearby.

Drive the Ohio River Scenic Byway across three states

You can pick up the byway in any of its three states.

The Illinois section runs about 188 miles, Indiana stretches about 302 miles and Ohio covers roughly 452 miles.

No fee applies to drive the road itself, but individual state parks, cave tours and Serpent Mound parking may charge admission.

Traffic thins out before July and after October, and fall brings strong foliage along the bluffs.

Key stops include Garden of the Gods, Cave-in-Rock, Clifty Falls, Marengo Cave, Falls of the Ohio, Angel Mounds, Marietta and Serpent Mound.

This article was created with AI assistance and human editing.

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