ultra-marathon running

For two decades, racers have gathered in southeastern France to begin a demanding footrace that takes them through three countries. Along the way, they have to conquer the tricky terrain of one of Europe's most imposing mountains. This title introduces readers to one of the most unique trail races in the world-and the competitors who have pushed themselves to the limit to complete the course. The title features informative sidebars, exciting photos, a map, a glossary, and an index.

The best mountain bikers on earth gather in Alberta, Canada, every summer to begin one of the biggest challenges their sport has to offer. This title introduces readers to a 2,745-mile (4,418-km) race that takes athletes along North America's Continental Divide before finally ending at the United States-Mexico border. The title features informative sidebars, exciting photos, a map, a glossary, and an index.

Faced with one of the toughest winter environments in the world, competitors in the Iditarod Trail Invitational need to have what it takes to survive the brutal conditions of the frozen Alaskan wilderness. This title introduces readers to a race that follows the same path as the famous Iditarod Trail Sled Dog Race, but instead features human competitors trying to make it through this month-long test on their feet, bikes, or skis. The title features informative sidebars, exciting photos, a map, a glossary, and an index.

By itself, any of the 4 Deserts races would be one of the longest ultramarathons in the world. Put together, the four events make up a series that challenges even the most elite long-distance competitors. This title introduces readers to these events, which take place throughout the year in South America, Africa, Asia, and Antarctica. The title features informative sidebars, exciting photos, a map, a glossary, and an index.

Every summer, runners gather in California's Death Valley to begin a race that covers 135 miles in searing heat. After beginning at one of the lowest points in the United States, competitors battle a scorching desert sun as they climb 8,300 feet (2,530 m) to finish at Mt. Whitney. This title introduces readers to an ultramarathon that event organizers call the "World's Toughest Footrace." The title features informative sidebars, exciting photos, a map, a glossary, and an index.

Every year in the heart of winter, runners, bikers, and skiers challenge themselves to cross 135 miles of terrain in the remote woods of northern Minnesota. This title introduces readers to one of the coldest ultramarathons on the planet, a race that begins in the "Icebox of the Nation" and only gets tougher from there. The title features informative sidebars, exciting photos, a map, a glossary, and an index.