This weekend, the strangest, simplest, and most brutal race in ultrarunning returns home to Tennessee. On Saturday, October 18, 2025, 75 of the world’s toughest runners will gather in Bell Buckle, the tiny rural town where Lazarus Lake’s peculiar idea, a race with no finish line, became a global phenomenon.
The Backyard Ultra World Championships, known as Big’s, begins at 7 a.m. local time. From that moment on, runners will complete one 4.167-mile loop every hour, on the hour, until only one person is left standing.
Everyone else will quit, collapse, or simply time out. It’s the sport’s purest test of endurance, and perhaps its most diabolical.
What Is a Backyard Ultra?
A Backyard Ultra is built on an absurdly simple format. Runners must complete a 4.167-mile loop every hour. If they finish early, they can rest, eat, or sleep until the next loop begins on the hour mark. If they fail to make it back in time, or fail to start the next lap, they’re out.
The race has no fixed finish distance, it continues until only one runner remains, who must complete one final lap solo to win. Everyone else receives a “DNF” (Did Not Finish), no matter how far they’ve gone.
The loop distance is deliberate, 24 hours equals exactly 100 miles. That mathematical neatness gives the event its rhythm, part running race, part psychological experiment.
At its heart, the Backyard Ultra isn’t about speed. It’s about resilience, pacing, and mental control, a contest of who can keep getting up, hour after hour, day after day, long after their body says stop.
When and Where
The 2025 Big’s Backyard Ultra World Championships begin on Saturday, October 18, at 7:00 a.m. Central Time, just after sunrise in Bell Buckle, Tennessee.
That’s 1:00 p.m. in the UK, 2:00 p.m. in mainland Europe, 8:00 a.m. on the U.S. East Coast, and 5:00 a.m. on the West Coast.
The race takes place on Laz Lake’s private property, affectionately called “Big Dog’s Backyard.” The course alternates between two loops, a trail loop through woods and fields during daylight hours, and a paved road loop at night. Both total exactly 4.167 miles, and both test runners in different ways, uneven terrain, humidity, and footing by day, darkness, chill, and mental fatigue by night.
How to Qualify
Reaching Big’s is a career-defining achievement in itself. The qualification process spans two years and dozens of countries.
The top 50 finishers from national Backyard Ultra championships earn automatic entry, representing their countries after the 2024 Team World Championships. Another 25 spots are filled from the At-Large list, made up of the best performances worldwide between August 2023 and August 2025.
Every one of the 75 starters has already run deep into triple digits of miles, many for multiple days straight. For most, Bell Buckle is less a race than a pilgrimage.
The 2025 Field: The Best of the Best
This year’s field is the strongest ever assembled, featuring names that have redefined human endurance.
- Phil Gore (Australia), The reigning world record holder with 119 loops (just shy of 500 miles). Calm, mechanical, and frighteningly consistent.
- Sam Harvey (New Zealand), The “assist” to Gore’s record run, known for his humor and mental toughness.
- Łukasz Wróbel (Poland), Europe’s breakout star after a 116-loop effort earlier this year.
- Harvey Lewis (USA), The American legend and schoolteacher, winner in 2021 and 2023, current Big’s course record holder at 108 loops.
- Ivo Steyaert and Merijn Geerts (Belgium), Team champions and endurance savants, both have broken the 100-loop barrier.
- Megan Eckert (USA), Women’s world record holder with 87 loops, returning to defend her title.
- Sarah Perry (UK), The UK’s women’s record holder (59 loops), making her debut on U.S. soil after winning the British championship in 2024.
All told, 42 nations are represented, from Iceland to India, Finland to Brazil, each sending its most durable, stubborn runner to test themselves against the best.
The Format and Schedule
The Backyard Ultra follows a ruthless rhythm.
- Every hour on the hour, a whistle blows.
- Runners have 60 minutes to complete a 4.167-mile loop.
- Those who return early can rest, eat, and reset, but must be back at the start line when the bell rings again.
- Fail to start, and you’re done.
The race continues indefinitely. There are no breaks, no timeouts, and no mercy.
Typically, dozens of runners will survive through the first 24 hours, reaching the 100-mile mark, but by day three, sleep deprivation begins to blur reality. By day four, hallucinations and breakdowns become common. Only a handful will see a fifth sunrise.
The event will be livestreamed from Bell Buckle, with commentary and interviews every six hours. Race updates, lap counts, and retirements will be tracked live throughout the weekend.
A Brief History
The Backyard Ultra began as an odd experiment in 2011. Race creator Gary Cantrell, better known as Lazarus Lake, wanted to design a format that tested not just the body, but the will.
It worked. What started with a few dozen runners in Tennessee has exploded into more than 500 Backyard Ultras across 85 countries.
Big’s has now become a world championship, alternating every two years between team and individual formats.
Past champions read like a who’s who of ultrarunning:
| Year | Winner | Loops | Assist |
|---|---|---|---|
| 2017 | Guillaume Calmettes | 59 | Harvey Lewis |
| 2018 | Johan Steene | 68 | Courtney Dauwalter |
| 2019 | Maggie Guterl | 60 | William Hayward |
| 2020 | Courtney Dauwalter | 68 | Harvey Lewis |
| 2021 | Harvey Lewis | 85 | Chris Roberts |
| 2022 | Piotr Chadovich | 76 | Harvey Lewis |
| 2023 | Harvey Lewis | 108 | Ihor Verys |
| 2024 | Scott Snell | 88 | Megan Eckert |
In just 15 years, Big’s has gone from a backyard curiosity to ultrarunning’s most legendary crucible, a race where sleep, nutrition, and psychology matter as much as speed.
Weather and Conditions
October in Bell Buckle brings cool mornings, warm afternoons, and chilly nights, near-perfect running conditions, if unpredictable.
Average highs hover around 70°F (21°C), with lows near 50°F (10°C). Rainfall is moderate, though showers can quickly turn the trail loops muddy and slick. Humidity drops compared to Tennessee’s summer, but misty mornings and damp evenings remain common.
The shifting temperature range adds strategy. Daytime requires hydration and sun protection, night demands layers, headlamps, and vigilance. Small mistakes, cold hands, wet socks, under-fueling, can end a runner’s weekend hours before their legs do.
Key Storylines to Watch
The Record Chase: Can Anyone Survive 120 Loops?
All eyes are on whether anyone can push past 119 loops, the current world record. Phil Gore and Sam Harvey are both in peak form, with Belgium’s elite duo and Poland’s Łukasz Wróbel waiting in the wings. Even Lazarus Lake himself believes this could be the year the 120-loop barrier falls. The potential for a five-day race is real.
Women on the Rise: Sarah Perry and Megan Eckert Lead the Charge
Only four women are on the 2025 start list, but each brings serious credentials.
Megan Eckert, the reigning women’s world record holder, is back to defend her 87-loop mark. The UK’s Sarah Perry, competing outside Britain for the first time, hopes to extend her national record and prove that women can hang deep into the final days.
In a format where patience often trumps speed, don’t be surprised if one of these women is still standing when only two runners remain.
The European Powerhouse: Belgium’s Backyard Empire
Belgium might be the deepest country in the field. Led by Ivo Steyaert and Merijn Geerts, the Belgians have turned the Backyard into a national pastime. Their precision, pacing, and teamwork could define the early days of the race, controlling tempo and ensuring someone from their squad goes deep.
Having won the team world title in 2024, Belgium’s contingent arrives with confidence and unfinished business, winning the individual crown.
The Return of Harvey Lewis: A Legend Chasing Immortality
Few names in ultrarunning command more respect than Harvey Lewis. The Cincinnati schoolteacher is one of the most composed competitors in Backyard history, a two-time winner who thrives on routine and optimism.
At 48, this could be his last great stand at Big’s. If Lewis can once again push beyond 100 loops, it would be another chapter in one of ultrarunning’s most enduring careers.
The Rising Stars: A Global Cast of Contenders
Poland’s Łukasz Wróbel enters as the wildcard, capable of 116 loops and showing no signs of slowing down. Japan’s Terumichi Morishita and Michitaro Mizuno bring the precision and pacing discipline that define Japan’s Backyard scene. France’s Nicolas Cointepas and Belgium’s Matthias Pelgrims are proven 80-plus-loop runners.
This year’s depth means there’s no safe bet, nearly half the field has run over 70 loops before. Expect surprises.
The Road Ahead
Fifteen years after its creation, the Backyard Ultra has become more than a race, it’s a philosophy. For Lazarus Lake, it’s about exploring the boundary between endurance and surrender.
“There’s no finish line,” he likes to remind runners. “You just keep going until you can’t.”
Every year, the world’s best arrive in his backyard to test that limit, knowing they won’t leave as “finishers.” Only one person will be declared the winner. Everyone else will fail, and that’s the point.
As the 75 runners toe the line this Saturday morning, they’ll begin a ritual that could stretch for days. Some will stop after a few loops, others after a few dozen. A handful may see a fifth sunrise.
No one knows when it will end. That uncertainty, that infinite horizon, is what makes Big’s so compelling.
By the time the final two runners face off under the Tennessee stars, the rest of the world will be watching one question play out in real time, how far can a human really go?
