5 Undiscovered Natural Wonders of the U.S.

Prepare to be wowed! These 5 above- and below-ground natural spectacles across the US rival the Grand Canyon or Niagara Falls.

Scenic view of waterfall and valley

by NEA Member Benefits

The sheer size and scale of the United States presents a treasure trove of travel opportunities for Americans travelling domestically. Our natural wonders and wildlife spectacles are some of the most awe-inspiring that you’ll find anywhere on the planet. Some sights, like the Grand Canyon, are world-famous. Others, such as the synchronous fireflies in the Smoky Mountains, are less conspicuous and require you winning a specific lottery to attend. Still, there are plenty of lesser-known places to see Mother Nature showing off that are accessible to everyone.

If you’re adventurous, delve below the earth’s surface to take a subterranean boat ride in Indiana, or stroll behind an underground waterfall in Tennessee. Be wowed by a nighttime rainbow in Kentucky, or by the sun becoming “eclipsed” by hundreds of cranes in Nebraska. You can even stir up your own bioluminescent glow in Washington.

If you’re ready to let the nation’s natural resources inspire you, visit these five under-the-radar spectacles.

1. Enchanted moonbows in Kentucky


Photo courtesy of www.kentuckytourism.com

In Kentucky’s Cumberland Falls State Resort Park, a full moon, a clear night and the mists of a waterfall combine to create a “rainbow” in the dark. The phenomenon stirs a sense of the mystical and dreamy, but is actually the product of science. 

The steep walls of the wide gorge, supporting the 68-foot-high, 125-foot-wide Cumberland Falls, capture large amounts of mist. If the moon is full or nearly full, the moonlight can create a lunar rainbow, also known as a “moonbow.” This nighttime counterpart to the sun’s rainbow may appear ghostly and white, but when it’s very cold and clear, the moonbow colors glow.

Other places in the U.S. have occasional moonbows, but at Cumberland Falls (also called “the Niagara of the South”), any full moon, year-round, could produce these memorable arcs. River rafting, horseback riding and hiking can all be enjoyed by day, before heading out as a moonbow-seeker at night. Admission to the park is free.

NEA member travel benefits: There are two airports you can fly into to get to the park: Blue Grass Airport (LEX) in Lexington and McGhee Tyson Airport (TYS) in Knoxville, each about 1.5 hours away. You’ll find deals on flights through NEA Travel: Flights. Click on the hotels page to see great prices like an average of $81 per night at Fairfield Inn Corbin, which has spacious rooms, a fitness center and indoor pool and complimentary breakfast. For an average of $105 per night you can get a room at Best Western Corbin Inn, which has rooms with kitchenettes and an outdoor pool.

Plan your itinerary: Cumberland Falls State Resort Park  | Corbin KY Tourism | Kentucky Tourism

2. Underground boat rides in Indiana

Myst’ry, in Bluespring Caverns near Bedford, Indiana, is the longest navigable underwater river in the U.S. A customized, 17-passenger electric boat offers 1.25-mile rides through caverns that are 1.75 million years old, which is still young by cave standards. With sculpted rocks overhead and northern blind cavefish and crawfish below, the hour-long voyage includes a guide who explains how caves are formed. Tours run between March 16 and October 31 ($22 for adults and $12 for children 3 to 15 years old). 

Photo courtesy of Indiana Office of Tourism

Above the cave, geology lessons can continue with a hike on an interpretive nature trail around a 10-acre sinkhole and a mining attraction, where you might find and keep fossils, arrowheads and gems from around the world. (Packages range from $5 to $25.) Nearby is the Land of Limestone Museum, which honors the local limestone that helped build many landmarks, including the Empire State Building and the Washington National Cathedral.

NEA members travel benefits: Book your flight to Indianapolis International Airport (IND), which is about 70 miles away, via NEA Travel: Flights. Next, check for hotels deals to stay at accommodations such as an Holiday Inn Express Hotel & Suites Bedford, an IHG Hotel, which averages $154 a night and has free WiFi and breakfast, plus an indoor pool and gym. Or, for an average of $78 a night, there’s the Quality Inn & Suites Bedford West, which offers complimentary breakfast.

Plan your itinerary: Bluespring Caverns| Limestone Country | Visit Indiana

3. A wildlife spectacle of cranes

Photo courtesy of Kearney Visitors Bureau

Every spring in Nebraska, almost half-a-million sandhill cranes pause in their annual journey to rest and revive in the Platte River Valley area of the Great Plains. Visitors can sign up to wait quietly in dark bird blinds for the sun to rise, as thousands of cranes spread their six-foot wings and rise into the sky to forage. Visitors can also perch before sunset and hear—and then watch—as thousands of birds return. The cranes may perform mating dances, contend with hawks or eagles or ride the thermals. 

The 45-year-old Crane Trust in Wood River offers wonderful crane-viewing opportunities, and the Rowe Sanctuary outside Gibbon also provides guided three-hour crane experiences and an overnight option. (Prices start at $15 and $50, respectively.)

Fort Kearny State Historical Park and a bridge at the Fort Kearny Recreation Area provide free public viewing of the cranes. As an added bonus while in the Great Plains, the prairie chicken mating dance is an unforgettable experience.

NEA member travel benefits: Through the NEA Travel Program, you can search for flights to Lincoln Airport (LNK), about 2 hours away. Look for affordable lodging options such as Days Inn & Suites by Wyndham Kearney, where for an average of $99 per night you can enjoy large, bright rooms with WiFi and breakfast included, or Candlewood Suites Kearney, an IHG Hotel, which averages $133 per night and has a fitness center and indoor pool.

Plan your itinerary: Visit Kearney | Visit Nebraska

4. The largest U.S. waterfall in a cave

Photo courtesy of the Chattanooga Convention & Visitors Bureau

If you want to stay cool and see cool things, head to Chattanooga, Tennessee, and visit Ruby Falls in Lookout Mountain. You can take one of the world’s steepest passenger railway to the mountaintop, where you can enjoy diverse attractions at Rock City. You can then go down the Incline Railway and walk deep into the earth, past stalagmites and stalactites.

Ruby Falls, located in one of the deepest commercial caves in America, is also the largest underground waterfall in the country. After descending 260 feet in a glass elevator, a colorful LED light show plays with the water that cascades 145 feet. The temperature stays 59 degrees year-round 1,120 feet below the ground of Lookout Mountain.

Leo Lambert, a local fan of caves, first saw the falls in 1928. The second time he visited, he took his wife Ruby and named the falls after her. By 1930, Ruby Falls was open to visitors. Admission prices range from $15.95 to $25.95 for Ruby Falls, and more if you want to take the Incline Railroad and visit Rock City.

NEA member travel benefits: Book a flight via NEA Travel: Flights into Chattanooga Metropolitan Airport (CHA) to earn NEA Travel Dollars. Next, check for hotels deals to stay at accommodations such as the art-filled boutique Hotel Indigo Chattanooga-Downtown, an IHG Hotel, for an average of $124/night or the train-themed independent historic hotel Chattanooga Choo Choo, which is inside the original Beaux Arts-style train station and has amenities like a pour-your-own beer hall inside an old train car and is adjacent to the Glen Miller Gardens built over the old train tracks. It averages $113/night.

Plan your itinerary: Lookout Mountain | Ruby Falls | Chattanooga Fun | TN Vacation

5. Washington’s bioluminescent glow

Photo courtesy of Owen Perry

Dip your paddles into the Pacific Ocean and create blue and green ripples of glowing wonder, as kayaks leave colorful wakes in the summer nighttime sea off Washington’s San Juan Island. The nutrient-rich waters can offer whale watching by day and underwater fireworks at night as tiny, single-celled plankton (called dinoflagellates) flash light when agitated.

Compared sometimes to the ocean’s version of the northern lights, shooting stars or fireflies, the bioluminescent show is different every night. Darting harbor seals may trail jet streams of color. A cross-hatch jellyfish that eats the plankton may glow extra brightly. Fingers swirling through the water paint illumination that then vanishes into the night.

Bioluminescence is best viewed when the moon is not full, the sky is overcast and there is no ambient light. Discovery Sea Kayaks in Friday Harbor of San Juan Island is one of the only outfitters there that offers guided bio-tours, so reserve in advance for the summer wonder ($140 for four-hour tours, participants must be 12 years or older). Locals say you can enjoy some of the light show for free from Jackson Beach.

NEA member travel benefits: Fly into Seattle-Tacoma International Airport (SEA) or Vancouver International Airport (YVR) by searching for airline tickets on NEA Travel: Flights. From either city, you’ll need to drive to Anacortes, WA, which is about 1.5 hours away, and then board a ferry to Friday Harbor. To find affordable accommodations, visit NEA Travel: Hotels to find deals like an average of $131 a night at the Orca Inn, which is basic but clean and is only seven blocks from the ferry. Friday Harbor Suites has much larger rooms, a café and a lovely garden with a hot tub outside, for an average of $238 a night.

Plan your trip: Visit San Juans | Experience WA

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