Wonders of the Ozarks: Plenty of fun a short drive away

THAYER, Mo. -- Peering from an overlook into the chasm of Grand Gulf State Park, it is easy to see why the area is known as the "Little Grand Canyon of the Ozarks."

Deeper than it is wide, the sheer rock walls drop some 130 feet, revealing the remnants of a collapsed cave. Part of the cave roof that didn't tumble down some 10,000 years ago remains as a 250-foot-long natural bridge.

The park is best visited in the winter when the leaves have fallen, allowing for a better view into its inner gorge. In any season, check the forecast before entering. A rainstorm within a mile can turn the gulf into a raging torrent.

"If you are walking down here, you need to be mindful of the weather," said Matthew Kantola, interpretive resource specialist at the park. "Flash floods are a reality. If you don't get out in time, you could be in for a bad day."

The impressive geology made Grand Gulf a solid choice for our "Seven Natural Wonders of the Ozarks," joining Greer Spring, Rocky Falls, Current River, Onondaga Cave, Johnson's Shut-Ins and Elephant Rocks.

With its pristine rivers, frothy waterfalls, surging springs and meandering caves full of fantastical formations, the Ozarks of southern Missouri is a mother lode of marvels thanks, largely, to what is known as karst topography.

Simply put, mildly acidic rain water moves through the fissures and fractures in the soluble limestone and dolomite. Over eons, the rock is eaten away into a subterranean maze of caves, sinkholes and springs, many of which feed their crystalline water into sparkling streams perfect for floating.

Grand Gulf is a dramatic example of the erosive power of water. Two creeks that drain about 28 square miles have carved out a mile-long canyon that leads through the natural bridge left by the collapsed cave. On the other side, the water flow disappears into an existing cave and joins an underground river that emerges some 8.5 miles away at Mammoth Spring in Arkansas.

Visitors can view the gulf from two hiking trails, with boardwalks and overlooks. Getting to the bottom takes a steep scramble.

The cave entrance is now plugged by sediment, but a century ago, explorer Luella Agnes Owen took a small boat onto the underground river and chronicled what she found in her 1898 book, "Cave Regions of the Ozarks and Black Hills."

Longtime visitors who returned to Johnson's Shut-Ins State Park when it reopened in 2010 found the shut-ins as good as new. (Tom Uhlenbrock ~ Missouri State Parks)

Swimming about her boat, she wrote, were "numerous small, eyeless fish, pure white and perfectly fearless; the first I have ever seen, and little beauties."

Greer Spring

The drive north from Thayer and Grand Gulf on the roller-coaster hills of Highway 19 brought us to another easy choice for the magnificent seven.

Greer Spring is not the largest of Missouri's springs -- Big Spring has that honor -- but was chosen because of its undisturbed setting deep in a secluded gorge. Halfway along the mile-long trail down the forested hillside, you hear the rushing of the spring water before you see it.

Greer pumps out 220 million gallons of water a day from two sources. The first flows from a small cave at the base of a gray bluff, tumbling over mossy boulders. The second, larger source is 300 feet downstream where the force of the water rushing from deep within the ground forms a frothy "boil" on the surface of an emerald pool.

The Current River, with its crystal water and deep pools, was the nation's first river-based national park.

The powerful surge creates a run of whitewater the rushes more than 1.4 miles to the Eleven Point River, nearly doubling its flow.

In the middle of winter, the 50-plus-degree temperature of the spring keeps the bordering plants lush and green. Mist floats over the water like spirits. An oasis in the drab of winter, early spring brings a profusion of delicate woodland wildflowers.

If Missouri has a Garden of Eden, this is it.

Rocky Falls

Continuing north on 19, a highway sign at Winona points the way to our next wonder, Rocky Falls.

Rocky Falls is not the state's largest waterfall (Mina Sauk Falls at Taum Sauk Mountain State Park is the tallest at 132 feet, but while Mina Sauk is spectacular after a rain, but is reduced to a trickle in dry months).

Rocky Falls has water most of the year, cascading down a 40-foot-tall series of chutes and ledges into a large pool that is one of the state's best swimming holes. Climbing the falls is a popular, if slippery, pastime.

The purplish rock is rhyolite, which was molten lava when it burst through the Earth's crust some 1.5 billion years ago. The ancient rock is harder than the surrounding dolomite, and "shuts in" the flow of Rocky Creek.

Shut-ins like Rocky Falls are a picturesque addition to the Ozark landscape, which brings us to wonder No. 4.

Johnson's Shut-Ins

On Dec. 14, 2005, the Ameren Missouri Taum Sauk Reservoir, perched on the top of Profitt Mountain breached, releasing 1.3 billion gallons of water that tore through Johnson's Shut-Ins State Park.

The namesake shut-ins was one of the premier playgrounds in the state park system. Generations of families had come to slide down its chutes and soak in its pools.

The shut-ins, suddenly, were buried in tons of rubble by the man-made catastrophe.

Five years later, the park re-opened after a laborious cleanup. By hand and by helicopter, the gravel, boulders and other rubble were removed from the shut-ins.

Visitors who returned to the park marveled to find the hard purplish rock -- the same rhyolite as at Rocky Falls -- unscathed by the beating. Ancient pinnacles still stood.

Johnson's Shut-Ins, natural wonder No. 4, was as good as new, or rather as good as old.

Current River

When Congress sought in 1964 to preserve America's free-flowing streams, the Current River was its first choice to receive protection. That makes it an easy selection for natural wonder No. 5.

Some 134 miles of the Current and its sister river, the Jacks Fork, were set aside as the Ozark National Scenic Riverways, the nation's first river-based national park.

From its start at Montauk State Park, the sun-dappled Current is a leisurely float beneath an arching canopy of trees. Cold enough for trout, the river is home to resident bald eagles, great blue herons, belted kingfishers and other wildlife.

The upper stretches from Montauk to Cedar Grove, Cedar Grove to Akers, Akers to Pulltite and Pulltite to Round Spring all are excellent day floats, passing gravel bars perfect for camping and turquoise springs that boost the river's flow.

Summer Saturdays are crowded. Spring, fall and winter, after a snowfall, are best for a quiet wilderness experience.

Onondaga Cave

With 6,300 caves to choose from, Missouri deserves its nickname as the Cave State. And Onondaga Cave State Park is a standout.

One of four state-owned "show" caves open to public tour, Onondaga has some 1.5 miles of passages decorated with pencil-thin soda straws, flowing drapery and giant columns where stalactites and stalagmites meet.

The cave has 68 known species, from tiny invertebrates to grotto salamanders to little brown bats that hang around the entranceway.

Tours follow a paved walkway leading through passages decorated with deposits called the Twins, the King's Canopy and the Rock of Ages. Big Room is 80 feet tall. The delicate floating formations in the Lily Pad room look like they were made from fine china.

Elephant Rocks

Our pick for natural wonder No. 7 is as much fun as it is fantastic.

The giant pink rock formations of Elephant Rocks State Park really do look like a chorus line of dancing circus elephants, when viewed with a child's eye. Walking around and under them, searching for the names chiseled in the granite by the quarry miners of old, is a great way to spend an afternoon.

Interpretive displays explain that the rocks were formed about 1.5 billion years ago during the Precambrian era when hot magma cooled into crystalline red granite, which weathered into the huge, rounded boulders.