This landscape looks like a winter wonderland. But these slopes are actually made of sand, not snow. The area in New Mexico recently became the 62nd national park in the U.S. It’s called White Sands National Park.
The dunes are made of a mineral called gypsum. Between 24,000 and 12,000 years ago, a lake covered the area. It was formed by rainwater carrying gypsum off nearby mountains. Over time, the lake dried up. It left behind a layer of gypsum up to 30 meters (100 feet) thick. Wind broke down the mineral into grains and piled them into dunes.
The dunes span 715 square kilometers (276 square miles)—an area nearly as big as New York City. That makes them the largest gypsum sand dunes on Earth! The sight of them is “otherworldly,” says park ranger Kelly Carroll.