Locals know where they are, and they probably would just as soon the rest of us didn't. But we waded in anyway and found perfect, little-known places to take a plunge: rock-rimmed waterfall pools, empty beaches, secluded riverbanks and more. The next 10 slides have some of our favorite Midwest swimming spots. Most of these destinations don't have lifeguards, so be sure to swim responsibly—especially if you're bringing little ones along.
Pictured: One of the swimming areas at Amnicon Falls State Park in Superior, Wisconsin.
Even though it's sanctioned as a county park, this St. Cloud-area preserve delivers thrills equal to the best secret swimming holes. Daredevils climb onto designated spots on rock walls and plunge into a cold, spring-fed pool that's as deep as 112 feet. Swimmers bob across the surface on rafts and inner tubes and do laps between points where the walls aren't as steep. A floating dock (left) makes getting out of the water easy and provides a platform for less-challenging cannonballs. (320) 656-3600; co.stearns.mn.us 
On a warm summer afternoon, waves with just the right amount of chill wash against this protected swath of white sand. Along the Upper Peninsula's north shore, Miner's Beach (left) is 12 miles east of Munising. The cliffs of Pictured Rocks National Lakeshore frame the beach, which is just a short walk from the parking lot. The best part: You'll likely have the beach to yourself even on the warmest summer days. (906) 387-3700; nps.gov 
Swimmers take turns beneath roaring cascades or slip into quiet, pine-shaded rock pools at this natural water park (left), a legacy of eons-ago earthquakes. This series of picture-perfect swimming spots 12 miles east of Duluth/Superior strings along the Amnicon River as it splits and flows around a small island. (715) 398-3000; dnr.wi.gov 
Visit Duluth 
Bluff Hole hides at the end of a path through a tunnel of trees where south-central Missouri's Jacks Forks River widens and takes its time. Gray-green shadows mark this classic swimming spot's deeper water at the base of a rock shelf, and gravel glints beneath the gin-clear shallows near the bank. On a quickly warming summer morning, the hole (left) feels like a discovery, and it has been for generations of local swimmers and visitors to Ozark National Scenic Riverways, about 140 miles east of Springfield. (573) 323-4236; nps.gov 
A small swimming beach edges a secluded natural lake (left) in this northeast Ohio park better known as a winter sports haven. Families picnic in woods beside the lake and spread out amid toys on the sand. But even on a hot Sunday afternoon, the number of swimmers totals only about 30, including little ones splashing in the shallows. (440) 564-2279; parks.ohiodnr.gov 
Beaches so white they recall the Caribbean rim this big blue reservoir (left) in far western Nebraska near Ogallala. Twenty miles long with more than 100 miles of shore when it's at capacity, the lake also draws boaters and anglers. (800) 658-4390; ilovelakemac.com 
This park appears like an oasis on western Kansas' plains (50 miles north of Garden City). Bluffs and wooded canyons surround a spring-fed lake (left) and swimming beach, with camping nearby. Canoe and paddleboat rentals are available. (620) 872-2061; kdwpt.state.ks.us 
At the southern border of Sleeping Bear Dunes National Lakeshore (30 miles west of Traverse City), this clear and shallow stream twists through woods and undulating sand dunes before emptying into Lake Michigan (left). Floaters in inner tubes and canoes glide past as swimmers splash. (321) 326-4700; nps.gov 
Families appreciate the broad beach and roped-off swimming area at White Breast Recreation Area along Iowa's largest reservoir near Knoxville (55 miles southeast of Des Moines). Neighboring North Overlook Beach (left) is great for a boat ride at sunset. (641) 828-2257; redrockarea.com 
(A version of this story appeared in Midwest Living® July/August 2007.)