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."
Score Breakdown
Based on distance, vertical gain per km, terrain difficulty, weather extremes, historical DNF rate, and race format.
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.
Experience ratings are based on runner reports, race reviews, community feedback, and editorial assessment. Scenery reflects the visual quality of the course. Organization covers aid stations, logistics, and communication. Community measures the atmosphere, inclusivity, and camaraderie among runners.
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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