Aquatopia at Camelback Resort in the Poconos boasts 125,000 square feet of water-filled fun, featuring seven pools (including a wave pool), 13 slides, an adventure river and a water play structure with nearly 100 gadgets and interactive elements and a 1,000-gallon dumping bucket. A highlight for thrill-seekers is Storm Chaser, one of the longest indoor, uphill water coasters in the USA. Visitors looking to relax can work on their tan year-round thanks to Aquatopia's transparent roof.
Photo courtesy of Camelback Resort

Guests of Massanutten in Virginia's Shenandoah Valley have eight waterslides, a leisure river, hot tubs and the state's first and biggest FlowRider surf simulator to choose from. Kid-friendly Frog Pond offers pint-sized thrills, while the whole family will enjoy the water cannons and gadgets of the Massanutten Meltdown play structure. An indoor/outdoor hot tub sets the scene for year-round relaxation.
Photo courtesy of Massanutten Resort

Great Wolf Lodge in Cincinnati packs a big punch of fun, with water coasters, raft rides, body slides, a wave pool, water fort tree house, lazy river and activity pool. Two giant hot tubs sooth cares away, while private cabanas give families a place to unwind.
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The Polynesian-themed Splash Lagoon is home to the biggest indoor wave pool in the Eastern United States, as well as other unique water-centric attractions. Guests can test themselves on the ropes course high above the water or float along the lazy river. For adrenaline-seekers, the Black Hole water slide submerges riders into total darkness. In total, the park features nine different waterslides – one tube reaches 40 miles per hour – as well as five on-site restaurant/bars and shops.
Photo courtesy of Splash Lagoon

Opened in 2009, Sahara Sam's Oasis features 58,000 square feet of indoor aquatic fun. Visitors can swim in Cleopatra's Cove indoor leisure pool, relax on the Congo Bongo lazy river, catch a wave on New Jersey's only surf simulator or tackle the Nile Mile, a super fast 350-foot body slide.
Photo courtesy of Sahara Sam's Oasis

Wilderness Resort at Wisconsin Dells features eight (yes, eight) different indoor and outdoor water parks all on site. Among the indoor parks, the 65,000 Klondike Kavern boasts thrill rides and a tall play feature; the 70,000-square-foot Wild WaterDome with its transparent roof actually allows guests to tan in the sunlight; the Wild West is the biggest indoor water park, with tubes, slides and bumper boats; and Cubby’s Cove has basketball hoops, geysers and a hot tub that looks out of the lake.
Photo courtesy of Wilderness Resort at Wisconsin Dells

Located just outside of family-friendly Pigeon Forge, Wilderness at the Smokies is home to Wild WaterDome, Tennessee's largest indoor water park. Exclusive to resort guests, the park features a transparent roof for year-round tanning, a 10,000-square-foot wave pool, a 1,000-square-foot hot tub, three-story ropes course, five-story family raft ride, waterslides, an aquatic play structure and a surf simulator.
Photo courtesy of Wilderness at the Smokies

Schlitterbahn Galveston Island, the third water park resort in the Schlitterbahn franchise, features 26 acres of aquatic action, including three indoor areas: Blastenhoff, Surfenburg and Wasserfest. This means no matter the season, guests can bob in a wave pool, face off on dueling uphill water coasters, shoot down waterslides, splash in a kids' activity area or hang ten on the Boogie Bahn surf ride.
Photo courtesy of Schlitterbahn Galveston Island

Timber Ridge Lodge in Lake Geneva, Wis. is home to a 50,000-square-foot indoor/outdoor waterpark, where visitors can zip down 35-foot slides, drift along a calm 500-foot lazy river, get moving in an activity pool or kick back and relax in an indoor/outdoor hot tub.
Photo courtesy of Timber Ridge Lodge & Waterpark

The indoor water park at Great Wolf Lodge in Concord is included for guests, with all the attractions you'd expect from a top notch water park. Park goers can choose from a variety of waterslides, zero entry wave pool, water basketball and a multi-level treehouse with 40 water features and a 1,000-gallon dump bucket.
Photo courtesy of Great Wolf Lodge