Since 2003, Henrik May has spent six months every year skiing down 400-vertical-foot runs – on Namibian sand. As the world's first dune-skiing outfitter, May has created a growing sport that now attracts adventurous skiers from around the world. During Namibia's dry season, from June through November, he leads ski excursions from the west coast resort town of Swakopmund into the 31,000-square-mile Namib Desert.

"In less than a minute, the wind blows your tracks from the dunes, so you never ski the same run twice," May says. "It's like melting into the terrain." May was born in the remote Thuringian Forest of East Germany and first learned to snow-ski at age four. "We skied down any hill we could find, even over grass or gravel if the snow had already melted."

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After moving to Namibia to help run a bed-and-breakfast, May noticed the dunes on the horizon resembled mountain peaks and decided to reconnect with his favorite sport – albeit on sand. He made his first dune descent in 2002. "My heart was beating from excitement, but as long as you keep your turns clear and movements controlled, the texture feels like fresh snow on a hard, icy track." In 2010, May set a sand-skiing world record when he reached 57 miles per hour while descending a 246-foot dune. "It can be quite dangerous," May says about speeding down dunes. "If you make a mistake, you can fall immediately – and feel like you're being tossed from a moving car onto a gravel road."