It’s a hot winter noon on a Monday and Camille Herron is asleep. She lies on a cot in a tent next to a flat dirt track. Lined with palm trees and white stone and desert grass, it loops two and a half miles along the lip of a large olive-green lake. Over the lake, towers a screen of steep mountains covered in bush scrub. It’s one resort among many in California’s Coachella Valley and the setting for Lululemon’s FURTHER event, a chance for 10 select women to run as far as they can in six days.

It’s the penultimate day, and her nap is stretching long – five hours – and the timer by the line is ticking – and Herron has less than 24 hours to run 48 miles. If she can will herself on, she’ll break a record that has stood for more than three decades.

Once the gold standard of what human beings could endure on foot, the six-day race predates both trail races and the modern marathon. In the 19th century, thousands of spectators lined up to watch these “pedestrians” walk six days – in the Empire Skating Rink at PT Barnum’s Hippodrome, where the Met Life Building now stands in lower Manhattan, and in fairs across the United States. Popular in Europe and America, they brought bettors and challengers and diversity. The first women’s six-day race took place in Chicago in 1876. According to Davy Crockett of the Ultrarunning History website, “more than 300 women” competed in these near week-long events in the 19th century. In 1880 a Haitian immigrant, Frank Hart, “wowed audiences at New York’s Madison Square Garden” by completing 565 miles in six days. He came away with $21,567, about $679,000 in today’s money.

Then came accusations of cheating, poisonings, the rise of the bicycle, and the final death blow, baseball. The 1980s saw a resurgence of the timed-format ultramarathons and the men’s six-day record was broken for the first time in a century. But it seemed a high-water mark had been reached. No one had come close to Yiannis Kouros’s 645 miles in 1988 and Sandy Barwick’s 549 in 1990, the men’s and women’s records respectively. “Their records have proven utterly resistant to successors,” says former Trans-America race director Jesse Riley.

Then in 2015, a lanky 5ft 9in runner from Norman, Oklahoma appeared on the ultramarathon scene. With an awkward gait, a wide smile, and an eccentric personality, Herron, a 2:37 marathoner, started an unprecedented streak. In 2017, she became the third American to win the Comrades Marathon, a storied 55-mile race in South Africa, and in 2023 won the Spartathalon, a 153-mile ultramarathon in Greece. She is the first athlete, male or female, to win both. That same year, she logged 270 miles around a 400m track in Bruce, Australia. She did so in 48 hours not only improving her own mark but becoming the first woman to hold an outright American record – for men and women – in distance running.

When the FURTHER event started last Wednesday, Herron was already the holder of multiple world records from 50 to 250 miles. A small crowd gathered under four towers of stage lights and rows of orange and white tents. The 42-year-old was in shades, a water bottle stuffed in the crotch of her shorts. On day one, she chugged a Coke float and ran 133 miles. Day two, she downed tacos and added another 113 miles. On 8 March International Women’s Day, she broke the American 48-hour road record for women. More would follow.

Each time Herron broke a record, she held her arms out wide, her hands pointing to the sky as if to say, “isn’t this incredible?” The fact that she is openly awed by what she does has at times made her a target in the ultrarunning community. Her whimsical pre-race mantra of “letting the magic come out” only adds to that. But it’s hard to argue with the numbers. And the numbers and records were piling up: a new 300km mark, the American 48-hour road record, a new 300-mile road record, the women’s 500km world record, the women’s 500 mile. When she completed the latter, she danced around the start line in pink compression socks, celebrating with high fives and hugs.

But the six-day mark was still out there – Barwick, 1990, 549 miles. As Herron slept during the day on Monday, questions started popping up on running forums and Facebook groups. “Bell lap!” wrote ultrarunning veteran and stats master Mike Dobies. “Did she save enough for a final push?”

The push comes at 2.30 in the afternoon. Herron is up and moving and soon the night will welcome cooler air and more miles. But after a few loops, she’s off course again. Resting again. “Run the routine,” she tells herself: Run, eat, hydrate, sleep, and repeat. But it’s getting harder to do any of those now. As Christian Griffith once said about his run across America, the goal is “way too close for way too long.”

Close is now 40 miles in 18 hours, and Herron is up and moving, recording 15-minute miles; for her, a walking pace, a death slog. Then another stop. She’s now in the realm of uncertainty the late ultrarunner Al Howie called the Ultra Daily News: “She’s dying … she’s back from the dead … she won’t make it.”

All through the night she keeps up the fight and at 3.30am Herron crosses the invisible threshold: 550 miles, a new world record, the Biggy, the six-day. However, the International Association of Ultrarunners, which ratifies the six-day race, doesn’t call any marks past a 48-hour run a world record. In the IAU’s phraseology, her performance is simply a ‘best’.

Herron promptly takes a nap, while praise flies in fast and furious. “It was just a matter of time,” says Trishul Cherns, head of the Global Organization of Multi-Day Ultramarathoners, an organization that tracks ultrarunning statistics. “Camille’s performance has proved that women who enter the game can compete on an equal footing with men.” Crockett says she “is the greatest woman ultrarunner ever, on tracks and roads.” And Barwick, the New Zealander whose record or “best” or accomplishment Herron broke, says she’s “in awe of her speed. A truly amazing performance, so courageous and inspiring to all athletes.”

But Herron isn’t done. As the sun rises over the Santa Rosa Mountains, she lifts herself to her feet once more. One more push. One more loop, then two, three. She reaches 900km, another record, then it’s over. In her wake are 11 world records recognized by GOMU and a world best performance by the IAU. Either way, the numbers on the LED screen read a clear 560.3 miles. Above is one word in all caps: FURTHER.