This Kentucky waterfall is one of only two places on Earth with “ghost rainbows”

Cumberland Falls’ Moonbow Phenomenon Transforms Kentucky Tourism

Cumberland Falls hides a sky secret most folks don’t know about.

Since the early 1900s, visitors have flocked to see its moonbow – a night rainbow that shows up when moonlight hits the mist. Postcards from 1920 prove people knew how rare this was.

The local inn even changed its name from Brunson Inn to Moonbow Inn in the 1930s to honor this marvel. What makes it special?

The falls face north at just the right angle, and only Victoria Falls in Africa shares this trait.

Kentucky parks now post yearly schedules so you can catch this ghostly white arch that reveals rainbow colors in photos. The story of Cumberland Falls shows how a quirk of nature can put a place on the map.

Postcards From The 1920s Showed People Already Loved The Moonbow

People visited Cumberland Falls to see the moonbow long before our time. By 1920, postcards showing this nighttime rainbow traveled across America.

Locals called the waterfall the “Niagara of the South” because it spans 125 feet wide and drops 68 feet. Early visitors watched in awe as a white light arc appeared on clear, full moon nights.

Native Americans thought both Cumberland Falls and nearby Eagle Falls were sacred places before hotels or parks existed.

Hotel Owners Spotted A Unique Business Opportunity

H. C. Brunson bought land near the falls in 1902 and opened the Brunson Inn. Tourism grew in the early 1900s when better roads made reaching the remote waterfall easier.

Hotel guests often talked about seeing strange light shows during full moons. Owners quickly realized they had something special.

No other place in America offered regular nighttime rainbows. The moonbow became a selling point that brought curious travelers from far away.

The Science Behind The Ghostly White Arc

Scientists learned that Cumberland Falls sits at an odd angle, facing north and flowing north. This position lets moonlight bounce off the water just right to create a nighttime rainbow.

The moonbow needs several things to appear: the right water temperature, lots of mist, clear skies, clean water, and certain wind patterns.

The falls create a perfect 42-degree angle between moonlight and water spray, making the moonbow show up when conditions line up.

Power Company Almost Destroyed The Moonbow Forever

The Cumberland River Power Company bought the Brunson Inn and nearby land for $190,000. They planned to build a dam upstream and send the river through a mountain tunnel.

This would shrink the mighty falls to a trickle and kill the moonbow. Worried businessman Robert Blair formed the Cumberland Falls Preservation Association.

As news spread about the threat, more people learned about the rare moonbow and wanted to save it.

A Chemical Company Heir Saved The Falls

T. Coleman DuPont stepped in during 1927 and offered $400,000 to buy more land around the falls.

As a Kentucky businessman and heir to the DuPont chemical fortune, he knew the moonbow location couldn’t be replaced. He made it clear the land should never generate electricity.

The Preservation Association convinced DuPont that Cumberland Falls needed protection. His offer meant the moonbow would shine for future generations.

Kentucky Created A State Park Despite The Governor

The Kentucky legislature overrode Governor Flem D. Sampson’s veto on March 10, 1930, and took the DuPont family’s gift of 539 acres.

After T. Coleman DuPont died later that year, his widow finished the donation to the state.

Cumberland Falls State Park opened on September 7, 1931.

The Civilian Conservation Corps built roads, trails, and facilities for people who came to see both the waterfall and its famous moonbow.

Local Inn Changed Its Name To Honor The Night Rainbow

The old Brunson Inn got a new name in the 1930s: the Moonbow Inn. This change showed how important the lunar rainbow had become for tourism.

As Cumberland Falls became an official state park, the moonbow gained more attention. The Moonbow Inn served as the main spot for travelers who came just to see this rare nighttime light show.

Hotel owners knew the moonbow brought guests who filled rooms and restaurants.

Scientists Found Only Two Places On Earth With Regular Moonbows

Researchers confirmed Cumberland Falls as one of only two spots worldwide where moonbows appear on a set schedule. The other location sits at Victoria Falls between Zimbabwe and Zambia in Africa.

Studies showed that Cumberland Falls holds a unique spot in the Western Hemisphere.

The exact placement of the waterfall creates the perfect angle needed for moonbows to appear monthly when conditions allow.

Park Rangers Started Publishing Moonbow Schedules

Kentucky State Parks began printing yearly moonbow schedules so visitors could plan trips ahead of time. Unlike other rare moonbows that show up randomly, the Cumberland Falls moonbow follows a pattern.

Tourism grew around knowing that the best viewing happens from two days before through two days after each full moon. Rangers picked the Upper and Lower Overlooks as the best spots to see the lunar rainbow.

Fires Destroyed The Hotels But Not The Moonbow’s Fame

Fire burned down DuPont Lodge in 1940, though workers rebuilt it by 1941. The old Cumberland Falls Hotel burned in 1947.

The Moonbow Inn caught fire in 1949, ending the era of moonbow-named lodging near the falls. Despite losing these historic buildings, the moonbow itself kept attracting visitors from around the world.

The natural phenomenon outlasted all the human structures built to serve its admirers.

Cameras Reveal Colors The Human Eye Can’t See

The Cumberland Falls moonbow looks like a ghostly white arch to people standing at the overlooks.

However, cameras set for long exposures capture what our eyes miss: the full rainbow spectrum of colors hidden in that white light. Photographers travel from across the globe to capture this rare sight.

Cumberland Falls maintains its status as the Western Hemisphere’s only predictable moonbow location, drawing scientists, nature lovers, and curious travelers who want to witness this celestial light show.

Visiting Cumberland Falls, Kentucky

Cumberland Falls at 7351 Highway 90 in Corbin offers free moonbow viewing with no park admission fees.

The park stays open 24 hours so you can catch this rare lunar rainbow that only happens here and at Victoria Falls in Africa. Your best chance is 2-3 days around each full moon.

Walk five minutes on the paved path from the visitor center to Upper Overlook for viewing. Summer visitors can take Rainbow Mist night raft rides for a closer waterfall experience.

This article was created with AI assistance and human editing.

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