The course at Mohican Wilderness combines everything great about mountain biking in Ohio: steep climbs, fast downhill, twisted turns and imposing rock gardens. The tough, rocky soil can hold a few inches of rain without caving, and the forest's so thick that much of the 10-mile trail feels like riding through a tunnel.

The course at Mohican Wilderness combines everything great about mountain biking in Ohio: steep climbs, fast downhill, twisted turns and imposing rock gardens. The tough, rocky soil can hold a few inches of rain without caving, and the forest's so thick that much of the 10-mile trail feels like riding through a tunnel.

Once around will test you. Twice through is pushing it. The winner of the 24 Hours of Mohican, held Saturday near Loudonville, lapped it 18 times. That's 180 miles and roughly 18,000 vertical feet in a single day.

Welcome to the world of endurance mountain biking, the sport's hottest trend and a grueling test of strength, stamina, strategy and skill.

"It's not a road course," said Ryan O'Dell, director of the eighth-annual Mohican event, as he added some caution tape to a hairy section. "This is serious mountain biking."

Ohio's only 24-hour contest works like an extended relay race, with solo riders and four-person teams attempting to finish the most laps during the allotted time. Consistency is key in both the day-long contest and the shorter 12-hour circuit, which also features categories for two- and three-person teams.

Last weekend, bikers came from across Ohio and as far as Utah to run themselves ragged on the jagged hills above the Mohican River.

"You've got to go out, have some fun and be calm and consistent," said Stuart Hunter, owner of Roll bike shops and a veteran endurance rider. "The first time you try to win is when you start making mistakes. A lot of races have been won at between one and five in the morning."

Most riders take several laps then rest for a bit, often sleeping in tents near the scorer's table. Four-person teams take turns riding and resting, optimizing strengths and fine-tuning bikes. As they ride into the night, everyone eats and drinks constantly.

In some ways, endurance mountain biking is essentially a blast from the past.

During the early 1900s, when cycling was among the most popular spectator sports in America, fans flocked to six-day races, in which solo riders or small teams would circle indoor velodromes to gain the most laps. Sixes, as they were called, would fill the bleachers at Madison Square Garden.

In most ways, though, endurance mountain biking is a different animal altogether. Even with a dry course and perfect weather, racers ride hard and fast over terrain that rips easily through spokes and shins, chain rings and quads.

To train, entrants ride as much as possible, especially at night, when a layer of fog can sink into the Mohican valley and cloak the course. Most prefer ultra-light bikes with high-end suspension, pedal clips, disc brakes and very bright lights. Many teams bring their own mechanic.

Besides a cold post-race beer, the thrill is gaining elevation, shedding it and the sight of the woods flying by at high speeds.

"It's a really fun course," said Mark Shellhamer, a rider from Warren who raced the 12-hour with two friends. "The first climb is probably the toughest in Ohio. It's one of the lesser-used trails in the state, but it's really good."

For more photos and race results, click to the Venture blog.