Big's Backyard Ultra is a Backyard (Last Person Standing) ultra marathon in Bell Buckle, United States. Elevation: 100m D+. Difficulty: brutal (Challenge Rating 34/100). DNF rate: 99%. Surface: trail. Established 2012.
Big's Backyard Ultra
Bell Buckle, Tennessee, United States
"One finisher. Everyone else DNFs. Run 6.7km every hour until only one person remains standing."
The original backyard ultra — the format that spawned a global movement. Last person standing wins, everyone else DNFs.
The Course
The original backyard ultra format created by Lazarus Lake. Runners complete a 6.706km (4.167 mile) loop every hour, on the hour. The last person standing wins. There is no set distance — the race continues until only one runner remains. Loops must be started on the hour; arrive late and you're out.
rolling
backyard
1
Runner Experience
Loop-based format with continuous access to a central aid area between laps.
A legendary finish line atmosphere. Big's Backyard Ultra is a bucket-list race with celebrations that match its reputation.
Race Day Weather
14°C
5° – 22°
70%
30%
Mid-October Tennessee weather — cool days, cold nights. Rain possible.
Stats & Records
2012
1
108 hours (67 laps / 449.3km)
Harvey Lewis (2023)
Entry
$350
May
instant
Lore & Trivia
Big's Backyard Ultra at Lazarus Lake's property in Bell Buckle, Tennessee is the format's world championship, but big-backyard-ultra may refer to similar events worldwide. The backyard format — 6.706km loops on the hour, last person standing — has become one of the fastest-growing race formats in ultra running history. From a single event in rural Tennessee, the concept has spread to every continent except Antarctica. The appeal is its radical simplicity: no qualifying, no entry fees (at most events), no distance targets. Just outlast everyone else.
- ▸ 6.706km loops every hour. Last person standing wins.
- ▸ No fixed distance — races have exceeded 700km.
- ▸ Format invented by Lazarus Lake in Bell Buckle, Tennessee.
- ▸ Hundreds of backyard events worldwide feed into the world championship.
- ▸ The format is growing faster than any other in ultra running.
- ▸ Sleep deprivation becomes the primary challenge after 24+ hours.
- ▸ Some events allow only water at the aid station — others are more generous.
A backyard ultra has no finish line. You don't cross something — someone else stops.
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Frequently Asked Questions
How long is Big's Backyard Ultra? +
Big's Backyard Ultra is a Backyard (Last Person Standing) ultra with 100m of elevation gain on trail terrain.
How hard is Big's Backyard Ultra? +
Big's Backyard Ultra is rated brutal with a Challenge Rating of 34/100 (Moderate). The DNF rate is 99%.
How do I enter Big's Backyard Ultra? +
Must have completed a qualifying backyard ultra distance. Invitation based.. An application or essay is required. Entry costs $350. with a maximum of 75 starters.
What is the weather like at Big's Backyard Ultra? +
Average temperature is 14°C (range 5°C to 22°C) with 70% humidity and a 30% chance of rain. Mid-October Tennessee weather — cool days, cold nights. Rain possible.
Are crew and pacers allowed at Big's Backyard Ultra? +
Crew access is allowed. Pacers are not allowed.
What is the course record for Big's Backyard Ultra? +
The men's course record is 108 hours (67 laps / 449.3km) set by Harvey Lewis in 2023.
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