KHANGAL NUUR, Mongolia — Amanda Charlton Herbert, 26, from Poland, has finished the longest horse race in the world, the Mongol Derby — a test of horsemanship and survival skills.

The derby, which is roughly 1,000 kilometers or 620 miles, started near Ulaanbaatar, Mongolia, on Wednesday, April 9. At 6:05 p.m. local time on Thursday, Aug. 17, eight days after beginning, Herbert crossed the finish line at Khangal Nuur.

“AC is a total petal — kindness and grace under pressure. She’s always smiling,” a member of ChoMedia filming the derby said of Herbert on Aug. 13.

Herbert, who rode by the call sign AC, was among a group known as the Magnificent Five, which included two other American riders, Leslie Wylie and Taylor Dolak, and two Australians, Lucy Taylor and James Lester.

Ed Fernon of Australia and Barry Armitage, South Africa, tied for the win on the seventh day. This year’s derby saw 42 people start the ride.

The Mongol Derby, confirmed by the Guinness Book of World Records to be the world’s longest horse race, crosses the Mongolian steppe, recreating Genghis Khan’s relay postal system.

Derby riders have up to 10 days to ride 620 miles, changing horses every 25 miles. They can only ride during daylight hours and travel between horse stations, known as urtoos. Riders may camp at these stations or they may endure the elements on the steppe.

Not like horses in Maine, Mongolian horses are “semi-wild,” free-ranging on the Mongolian steppe. Herdsman handle them minimally, never stalling or corralling them.

Just mounting, staying on and keeping track of the little horses can be dangerous and challenging. One of the riders finishing with Herbert, Wylie of Tennessee, was dumped by her horse. Wylie lost her equipment and was forced to ride many miles without stirrups.

A broken ankle and many broken ribs have tested the riders. Seven pulled out of the race as of the ninth day, many of whom were injured, with one suffering from hypothermia.

Mongol Derby officials considered this year’s weather conditions to be the most extreme they’ve seen, tweeting torrential monsoons that delayed race starts as “biblical.”

Finishing this ride is something few people can boast.

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