When the heat of summer descends, millions of visitors head to America's water parks to cool off. We asked our readers to vote for the 10 best outdoor water parks in the country for the ultimate day of sun and fun, and the results are in.

No. 10: Schlitterbahn - New Braunfels, Texas. Over three miles of tubing and seven kids' areas complete this popular water park between Austin and San Antonio. It sets itself apart with three uphill water slides (a novel concept invented by Schlitterbahn), as well as The Falls, a 3,600-foot-long lazy and not-so-lazy river – one of the world's longest water park rides.

No. 9: Noah's Ark - Wisconsin Dells, Wisconsin. An apt name for a water park of Biblical proportions, Noah’s Ark is the apex – the largest water park in the United States. Guests enjoy bodyboarding on the Surfin’ Safari, spooky thrills (four choices in all) on the deep, dark Black Thunder slide or hair-raising chills on Point of No Return, with its no-joke, near-vertical plunge. Two lazy rivers, two wave pools, four kids' play areas and bumper boats are the icing on the cake.

No. 8: Adventure Island - Tampa, Florida. In Tampa, thrill-seekers can tackle Colossal Curl, a thrill slide at Adventure Island bringing up to four riders high above the action for a weightless experience that merges funnel and wave for an action-packed descent. Back on the ground, Paradise Lagoon’s 9,000 square feet of slides and waterfalls offer lots of adventure on terra firma – unless you choose to cliff jump off its 20-foot platform, of course.

No. 7: Rapids Water Park - Riviera Beach, Florida. Rapids Water Park, the largest water park in South Florida, comprises 30 sun-kissed acres dotted with some 42 water slides and attractions. That includes the Black Thunder dark vortex funnel, Brain Drain vertical plunge, FlowRider surf simulator and Riptide Raftin' family raft ride.

No. 6: Island H2O Live! - Kissimmee, Florida. Island H2O Live! Water Park is an outdoor attraction in Kissimmee, Florida, just south of Orlando. Guests can enjoy the shade of a full-service cabana, float down a lazy river or experience the thrills of body slides, high-speed rafting, tube slides and six-lane racing.

No. 5: Dollywood's Splash Country - Pigeon Forge, Tennessee. Dolly’s Smoky Mountain oasis offers up more than 24 slides and thrill rides for all ages at Splash Country. The littlest guests enjoy loads of interactive playtime in places like the Cascades – a lagoon-style pool where hidden misters, bubblers and secret slides make for fun discovery. Thrill-seekers, on the other hand, revel on rides like the RiverRush. It’s four stories of family fun on a water coaster with multiple drops, twists and turns.

No. 4: Water Country USA - Williamsburg, Virginia. Welcome to Virginia’s largest water park, where little ones enjoy colorful oases like the Critter Corral and the space-themed H2O UFO interactive water playground, while the big kids (adults included) feed their need for speed on serious drop slides like Vanish Point. On Jet Scream, single riders soar on 400-foot flumes, reaching speeds of 25 miles per hour.

No. 3: Splashin' Safari - Santa Claus, Indiana. It may be in Santa Claus, Indiana, but Splashin’ Safari’s about as far from the North Pole as you can get, offering myriad thrills to cool guests off in the summer heat. Families who thrill-ride together will revel catching actual air on Mammoth – a water coaster so massive its seven-story bulk takes up more than three acres! Multiple drops employ cutting-edge technology, lifting up to six passengers to plunge again and again and again.

No. 2: Lost Island Waterpark - Waterloo, Iowa. At Lost Island Waterpark in Waterloo, Iowa, park-goers can take the plunge at Lost Soul Falls, catch a wave in Tsunami Bay, float the Kailahi River, play some volleyball in Blue Iguana Lagoon or ride one of the world's only hydromagnetic water coasters, Wailua Kapua.

No. 1: Aquatica Orlando - Orlando, Florida. SeaWorld’s first and most popular water park, Aquatica Orlando, draws 1.5 million visitors per year while seamlessly integrating sea life into rides. Its signature attraction, Dolphin Plunge, is an enclosed tube slide that passes through a pool of playful, black and white Commerson’s dolphins. Guests can also take a leisurely raft ride down Loggerhead Lane through colorful exotic fish. Aquatica's South Seas theme is further enhanced by 60,000 lush, tropical plants covering its 60 acres.