If you’ve ever had the chance to see a waterfall up close, you know what a beautiful — and powerful — sight it can be. Depending on the size and location of the waterfall, thousands and thousands of gallons of water can cascade down the side of a mountain every second of every day.

A waterfall is exactly what it sounds like: a place where water falls steeply from a height. Waterfalls form when swiftly moving water cuts through and wears away soft rock through a process called “erosion.”

It can take thousands of years for a waterfall to form. The spot where a waterfall collects at the end of its fall is called a “plunge pool.”

Waterfalls continue to change constantly, although the changes can be hard to see with the naked eye because they occur slowly over time.

The waterfalls that exist today will be around for a long time, but they will eventually disappear. As erosion continues, waterfalls keep retreating backward until all that’s left is a gorge.

It takes just as long for a waterfall to disappear as it did to appear in the first place. For example, Niagara Falls retreats at a rate of about 3.3 feet per year.

The tallest waterfall in the world can be found in Venezuela. Angel Falls (called Salto Ángel locally) is more than 3,200 feet high with an uninterrupted drop of 2,648 feet (that’s approximately a half-mile!).

Angel Falls drops over the edge of the Auyantepui mountain in the Canaima National Park. Angel Falls was unknown to most of the outside world until 1933, when American pilot Jimmie Angel flew over it while searching for valuable ore in the area. The falls were named after Angel.

Although it’s one of Venezuela’s top tourist attractions, a trip to Angel Falls is not your average sightseeing trip. Because the falls are located in a remote jungle area, one must take a flight to a local camp before riding in a boat along a river to the base of the falls.

If you’re in the area, it’s definitely worth seeing, though. Angel Falls is currently in the running to be named one of the New7Wonders of Nature.

If you want to see a waterfall, you don’t need to travel around the world. There are probably many beautiful waterfalls not far from where you live.

For example, the World Waterfall Database lists nearly 5,000 waterfalls in North America alone.

In case you were wondering, the continental United States boasts its own tall waterfalls. Many people consider Yosemite Falls in California to be the tallest waterfall in the United States with a vertical drop of 2,425 feet.

Others believe the tallest U.S. waterfall is Colonial Creek Falls in Washington, which plunges 2,568 feet. Unlike the sheer drop of Yosemite Falls, Colonial Creek Falls plunge in 13 different, gradual steps and thus are not as impressive to look at as Yosemite Falls.