Missouri's Waterpark Of Volcanic Chutes Invites Splash-Filled Adventures With Spacious Campsites

Nestled in the ancient rocks of one of the world's oldest mountain ranges lies a unique state park where visitors can slide down volcanic chutes into clear, cascading waters. Johnson's Shut-Ins State Park is also known as "Mother Nature's waterslide," and for good reason: The park's namesake attraction is a series of "shut-ins," volcanic rock formations that alter the flow of the Black River, forcing its cool, turquoise waters to keep moving through nooks, crannies, and crevasses. The result is spectacular: Natural water slides down slippery ancient rhyolite rock lead into deep plunge pools, and evocative blue-gray and pink cliffs form the perfect place to jump in this state park where the splash-filled adventures are endless.

Less than a 2-hour drive from St. Louis, Johnson's Shut-Ins is located in the rugged wilderness of the 1.5 billion-year-old St. Francois Mountains, an area that has retained the wild characteristic that initially repelled white settlers coming from the east. Osage hunters once lived here, until the Johnston family arrived from Appalachia and decided to homestead in the area, building their farm in 1829 (the "t" in their name was lost over the generations). Visitors have been able to enjoy all of the park's offerings since 1955, when local conservationist Joseph Desloge, who had acquired the land, donated it to the state. 

It's not just about the shut-ins, though. This park is known for its spacious and well-maintained campsites, a handful of trails that range from easy and ADA-accessible to strenuous, and its diverse flora, in particular. After all, Johnson's Shut-Ins is home to more than 900 species of flora — nearly a third of the total native plants in Missouri — which is just one reason why this mountainous area is just as scenic and stunning as Missouri's famed Ozarks.

What exactly is a "shut-in?" Well, yes, it's a guy role-playing "Grey Gardens" with 14 cats who hasn't left his house since 1987, but in this case, it's a specific geological feature created by volcanic activity. The St. Francois mountains were formed by volcanoes that erupted molten ash, which then cooled into rhyolite, a smooth gray, and sometimes pinkish rock that's hard and erosion-resistant. These volcanic rock formations altered the flow of the Black River, which is now more shut in and forced to wind its way out through crevasses and openings in the rock. Et voilà, you have a natural water park where you can slide down rocks that are over a billion years old.

Part of what makes Johnson's Shut-Ins so special is the wildness of the area, so a swim in the shut-ins requires a little bit of preparation. There's no lifeguard, so swim at your own risk, and bring a life jacket if necessary, as the water currents can be strong. Water shoes are highly recommended, since the smoothness of the rocks that makes them so fun to slide down also makes them a bit tricky to navigate. Food or drink are not allowed at the shut-ins, with the exception of reusable water bottles. The water is clear but cold, and it's a great place to snorkel or cliff jump if you're feeling extra adventurous. While you can find Missouri's canoeing capital in the Ozarks, note that due to the structure of the shut-ins, you'll need to leave your canoe or kayak at home — this area is for swimming only.

In 2005, a breach in the Taum Sauk reservoir sent 1.3 million tons of water rushing down Proffit Mountain and into Johnson's Shut-Ins. It took just 12 minutes, but the devastation was massive: The landscape was stripped, the shut-ins were filled with debris, and massive boulders were deposited in the former campground. The park was transformed completely, and it was closed for five years for cleanup and renovation. As a result, it's now home to a well-equipped campground USA Today named as the No. 1 Best State Park for RVing/Camping in 2022, another reason Johnson's Shut-Ins is one of Missouri's beloved mountain park paradises. The new camping area is farther removed from the shut-ins and includes additional flood protection measures. The old campsite, by the way, is now the boulder field that's in front of the visitor center; all those boulders were carried down the mountain by the flood, a vivid illustration of the disaster's power.

Camping options include RV hookups, primitive tent sites, and basic cabins that sleep up to six people but don't have running water or toilets. There are equestrian sites as well, and more luxurious housekeeping cabins with kitchens and bathrooms. Perhaps unsurprisingly, Johnson's Shut-Ins is an especially popular destination in the summer, as it offers an opportunity to cool off like no other. So, it's best to reserve your campsite in advance; camping rates range from about $15 to $35 in the high season of April through October, while camper cabins cost around $80. Or consider visiting in the off-season — spring or autumn — to enjoy peace, solitude, and the almost disturbingly stunning colors of blooming wildflowers or fall foliage against the backdrop of this volcanic waterpark.