Few sights on earth pack more power than waterfalls. Waterfalls scream adventure, danger and beauty.

They are also a searing reminder of how much wilderness we have lost. As part of our Earth Week series, we honor their poignant power.

We’ve shown you waterfall kayaking, waterfall diving and waterfall rappelling. Now, as per the World Waterfall Database, here is a look at the five largest waterfalls in the world.

Khone Falls

35,376 ft. (avg. width), Mekong River, Ban Hang Khone, Laos

Trivial Pursuit questions do not come much harder than the name of the largest waterfall in the world. For starters, it lies in sleepy, landlocked Laos in South East Asia. Additionally, it officially has a French name, Les Chutes de Khone – presumably because Laos was once a French colony. Khone Falls represents the main barrier to navigating the river it graces, the mighty Mekong, which just makes the natural marvel more impressive.

Wonder why it does not crop up in wonder-of-the-world lists more often? Khone Falls splits into seven thunderous channels and stretches no less than 6 miles in width, making it the planet’s widest waterfall. Despite the cascade’s immense size, during monsoon season, the flooding river gobbles it, leaving nothing more than a few choppy pleats. The obscure phenomenon is even more bizarre and extraordinary than it looks. Better still, according to Encyclopedia Britannica, Khone has the greatest volume of the world’s waterfalls – its 2,500,000 gallons per second are nearly double what Niagara Falls pumps out.

Para, Salto

18,400 ft. (avg. width), Rio Caura, Bolivar, Venezuela

The waterfall ranked the world’s second biggest by the World Waterfall Database is set in a part of the world with a potent connection to monster cascades – South America. Para Falls, however, has a very strange story surrounding it. You would think that, as the second largest waterfall, Para would be heavily documented and recorded. Like the region’s legendary Amazonian Indians, however, Para is marked unconfirmed. The World Waterfall Database just says it is known to exist, but its stature and location have not yet been verified. The second largest waterfall in the world should make enough of a splash to be confirmed, as pictures across the internet show that it is certainly very big indeed. It reportedly stretches 230 feet tall, dropping in two steps, and stretching as much as 3 1/2 miles wide, separated by a string of islands. The falls give on to the Orinoco River.

Guaira, Salto Del Parana

15,840 ft. (avg. width), Brazil

The third landmark on our list of largest waterfalls in the world does not actually exist. That fact must make it quite hard to include in a top-five ranking of monster waterfalls, you might think. As explained in the database, in appealing fairy tale language, “once upon a time, there was a massive waterfall. Sadly, it was flooded by the reservoir of a massive dam in 1982.” The database adds that “it’s a shame” that the dam could not be shortened in height to let Guaira continue its existence. This list was supposed to be jolly and exhilarating but Guaira – or the Itaipu Dam reservoir now – underlines just how badly the Earth is in need of preservation. Can the hydropower that the area generates be worth the loss of what must have been one of the most spectacular sights on the planet?

Kongou Falls

10,500 ft. (avg. width), Gabon

The Kongou Falls is another tricky one. “This waterfall is known to exist but its stature and location have not yet been verified by the World Waterfall Database,” the database says. According to National Geographic, Kongou Falls is a string of falls along the Ivindo River – the key tributary of the Ogooue river that flows through Gabon. National Geographic pegs Kongou Falls as exceeding 185 feet at its tallest drop.

The 2-mile-wide cataract slices through Gabon’s Ivindo National Park, National Geographic states, also noting that the falls’ churning waters kick up foam and spray. Well, they would. The massive, but mysterious, marvel adds to the feeling that our planet is less charted than you might think. Sadly and predictably, Kongou Falls may not be around in any shape for much longer though. The reason: the authorities of Gabon are more interested in energy generation and mineral extraction than sustaining its beauty, according to one report. Time will tell.

Iguazu

8,800 ft. (avg. width), Cataratas Del Parana, Argentina

Here’s a mammoth waterfall that definitely exists and looks set to carry on existing. In a bonus, you might well know it. Meet Iguazu. One of the largest waterfalls of South America and the world, Iguazu overlaps the border of Brazil and Argentina. It plunges a total of 269 feet along the Rio Iguazu where the river twists around a headland and spreads out over a shelf, cleaving into hundreds of separate falls. Most of the roiling water vanishes down a mighty landmark memorably known as the “Garganta del Diablo” (the Devil’s Throat).

The World Waterfall Database raves about Iguazu, which matches huge volume with immense width and a steep drop. The resulting mega-cascade boasts proportions that can’t be equaled by more than a sprinkling of rival waterfalls around the globe. The database notes that photographer Yoshikazu Shirakawa devoted almost a third of his epic book, “The World’s Hundred Greatest Waterfalls, Vol. II,” to Iguazu Falls – for good reason, the database reckons. “There really is no question in our minds, Iguazu Falls is the world’s greatest waterfall,” it says.