Missouri’s billion-year-old volcanic mountains hide waterfalls and wild swimming holes

Ancient peaks above the Ozarks

Most people don’t think of Missouri when they think of volcanoes.

But deep in the southeast corner of the state, a range of peaks rises above the Ozark Plateau, and every one of them started as fire and magma over 1.4 billion years ago.

The St. Francois Mountains hold the state’s highest point, its tallest waterfall, and some of the oldest exposed rock you can touch anywhere in North America.

Six counties, 133 named peaks, and enough wild ground to fill a week. The best parts take some walking to reach.

Born from fire and ancient magma

The rock beneath your feet here is pure igneous, forged by volcanic eruptions and magma that cooled deep underground.

Rhyolite and granite dominate the range, and you can see evidence of those ancient blasts in ring-shaped fault systems and thick layers of volcanic ash rock.

The rest of the Ozarks formed from eroded sedimentary layers, but not these mountains. Taum Sauk and its neighbors were volcanic islands in ancient seas and never went under.

The range was already twice as old as the Appalachians when those mountains first started rising. Geology students travel here from across the country to study what’s left.

The highest point in Missouri

Taum Sauk Mountain tops out at 1,772 feet above sea level.

You can reach the summit marker from the parking lot on a short, wheelchair-accessible path, so the highest point in the state is one of the easiest to stand on.

If you want more of a challenge, the Mina Sauk Falls Trail runs a rugged three-mile loop through the summit area. Along the way, open rocky glades give you wide views of the surrounding St.

Francois peaks. The park costs nothing and stays open year-round.

132 feet of falling water

Mina Sauk Falls drops 132 feet over a staircase of rocky ledges into Taum Sauk Creek.

You reach it from the summit area along the same rugged trail, and the best time to go is spring or right after a heavy rain, because the falls only flow when the weather cooperates. From the top, you can look down over the whole cascade.

If you can handle some scrambling, the base gives you the best view.

About a mile past the falls on the Ozark Trail, Devil’s Tollgate waits, an eight-foot-wide slot cut through 50 feet of rhyolite that towers 30 feet above you.

Swim through carved volcanic rock

Johnson’s Shut-Ins State Park spreads across 9,432 acres along the East Fork of the Black River. A shut-in forms where hard volcanic rock squeezes the river into a narrow channel.

Over time, water carved that rock into smooth chutes, plunge pools, and small waterfalls. In warmer months, you can splash and swim right through them.

A paved quarter-mile boardwalk leads to an observation deck if you just want to watch. The park also has camping, hiking trails, and horseback riding, so you can make a full day or weekend out of it.

Boulders the size of buildings

Elephant Rocks State Park earns its name from massive granite boulders that line up end to end like circus elephants on parade.

The granite cooled from magma about 1.5 billion years ago. The biggest boulder, nicknamed Dumbo, weighs 680 tons, stands 27 feet tall, and stretches 35 feet long.

You can climb on the rocks, squeeze through gaps like Fat Man’s Squeeze and The Maze, and let your kids scramble freely.

The one-mile Braille Trail here was the first in Missouri’s state parks built for visitors with visual and physical disabilities. The park is free and open all year.

Granite that built a city

Workers started quarrying granite from the Elephant Rocks area in 1869, and the reddish-pink stone, sold commercially as Missouri Red, shipped across the country.

Some of it ended up in the piers of the Eads Bridge in St. Louis. More went into St. Louis City Hall.

Smaller blocks were cut into paving stones and laid on city streets and the riverfront wharf.

You can still see the ruins of the old railroad engine house from that era standing inside the park. A spur trail off the Braille Trail leads to an overlook of the abandoned quarry.

A stone honeycomb on a hilltop

Hughes Mountain holds something you won’t find in many places on Earth.

Ancient lava cooled here and cracked into polygonal columns with four to six sides, each up to three feet tall.

From above, they look exactly like a giant honeycomb made of stone, which is why the formation goes by the Devil’s Honeycomb. This kind of columnar jointing in rhyolite is extremely rare worldwide.

The same geological process created Devils Tower in Wyoming and the Giant’s Causeway in Ireland.

A 1.4-mile trail from the parking area on Highway M takes you to the summit and the formation itself.

A trail through deep time

Pickle Springs Natural Area covers about 256 acres and holds a National Natural Landmark designation. The two-mile Trail Through Time winds past sandstone cliffs, slot canyons, double arches, and hoodoos.

Over 250 plant species grow here, including rare glacial relics from a time when Missouri’s climate ran colder and wetter.

Cool, moist canyon walls shelter more than 40 species of liverworts, one of the richest collections of those primitive plants in the state. One crustacean species found here exists nowhere else on Earth.

The trail crosses bridges over Pickle Creek and Bone Creek and climbs to Dome Rock Overlook for long views.

Missouri’s only real whitewater

Millstream Gardens Conservation Area holds the Tiemann Shut-Ins, where the St. Francis River crashes through granite boulders and creates the only true whitewater kayaking run in the state.

Each spring, the Missouri Whitewater Championship races take place right here, and the rapids carry names like Big Drop, Cat’s Paw, and Rickety Rack. You don’t have to paddle to enjoy it.

A paved, accessible trail leads down to an overlook area where you can watch the water pound through the rock. Oak, hickory, and pine woodland surrounds the shut-ins, and deer and turkey move through the trees.

Wilderness trails and old-growth forest

The Bell Mountain Wilderness covers 9,143 acres inside the Mark Twain National Forest, with about 12 miles of trails cutting through it. Congress designated the area in 1980.

Bell Mountain itself rises to 1,702 feet, the second-highest peak in the range, and rocky glades at the summit open up to wide views.

South of there, Sam A. Baker State Park spreads across 5,323 acres along the St. Francis River and Big Creek, with fishing, floating, and trails.

The park’s 14-mile Mudlick Trail climbs through old-growth forest past stone shelters the Civilian Conservation Corps built in the 1930s.

A separate Shut-Ins Trail brings you to seasonal waterfalls dropping off boulders into clear pools.

Rivers and forests connect it all

The Ozark Trail links many of the region’s parks and wilderness areas, so you can cover miles of varied ground without doubling back. Three major rivers run through the range: the Black, the St.

Francis, and the Castor. At the Castor River Shut-Ins, another set of pools and rapids carved through pink granite waits for you. The land around the St.

Francois Mountains sits within the largest unbroken forest in Missouri and the lower Midwest.

Small towns like Ironton, Arcadia, Fredericktown, and Caledonia ring the mountains and give you a place to eat, sleep, and fuel up. Every Missouri state park in the region is free to enter.

Explore the St. Francois Mountains in Missouri

You can reach the St. Francois Mountains in about two hours by driving south from St. Louis.

Five state parks cluster within the range: Johnson’s Shut-Ins, Taum Sauk Mountain, Elephant Rocks, Sam A. Baker, and St. Francois. All of them are free to enter.

The region also includes conservation areas, wilderness lands, and sections of the Ozark Trail running through the Mark Twain National Forest. Camping and cabins are available at several parks.

Johnson’s Shut-Ins State Park sits at 148 Taum Sauk Trail, Middle Brook, Mo.

Check the official website for seasonal hours, campsite reservations, and trail conditions before you go.

This article was created with AI assistance and human editing.

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