Big Dog's Backyard Ultra is a Last Person Standing ultra marathon in Bell Buckle, United States. Elevation: 100m D+. Difficulty: brutal (Challenge Rating 37/100). DNF rate: 99%. Surface: trail. Established 2012.
Big Dog's Backyard Ultra
Bell Buckle, Tennessee, United States
"One loop per hour. Last person standing wins. The original backyard ultra from the mind of Lazarus Lake."
The original backyard ultra — a 6.706km loop every hour until only one remains. Created by Lazarus Lake. Zero finishers, or exactly one.
The Course
The original backyard ultra format invented by Lazarus Lake. A 6.706km (4.167 mile) loop every hour until only one runner remains. The course is a mix of trail and gravel road through rural Tennessee farmland with gentle rolling hills.
rolling
backyard
1
Runner Experience
Standard aid station support with food, drinks, and basic medical assistance at regular intervals.
A legendary finish line atmosphere. Big Dog's Backyard Ultra is a bucket-list race with celebrations that match its reputation.
Race Day Weather
14°C
6° – 22°
65%
30%
Tennessee October — pleasant days, cool nights. Weather can be variable with occasional rain.
Stats & Records
2012
1
108:00:00
Harvey Lewis (2023)
Entry
$200
January
instant
Lore & Trivia
Big's Backyard Ultra is the original — the race that Lazarus Lake created in his own backyard in Bell Buckle, Tennessee, that spawned a global format revolution. The concept is elegant in its cruelty: runners complete a 6.706km loop (exactly 4.16667 miles, so that 24 loops equals 100 miles) every hour, on the hour. If you're not at the start line when the whistle blows, you're out. The last person still running wins. There is no fixed distance — the race ends when only one person remains. Records have stretched past 100 hours (670+ km). The format has exploded globally, with hundreds of backyard ultras now held on every continent, all feeding into Big's as the world championship. The beauty of the format is its democracy: you don't need to be fast, just relentless. Some of the best backyard runners in the world are not competitive ultramarathon racers — they are simply the people who refuse to quit.
- ▸ The original last-person-standing race, created by Lazarus Lake in Bell Buckle, Tennessee.
- ▸ Loops are exactly 6.706km (4.16667 miles) so that 24 loops = 100 miles.
- ▸ There is no fixed distance — the race continues until only one runner remains.
- ▸ Records have exceeded 100 hours and 700km.
- ▸ Hundreds of backyard ultras worldwide now feed into Big's as the world championship.
- ▸ The format has been called the most democratic in ultrarunning — speed matters less than will.
- ▸ The "yard" at Big's is Lazarus Lake's actual property in rural Tennessee.
- ▸ Runners sleep in tents between loops — the challenge is getting up again.
- ▸ Taps is played when a runner drops out, just like at Barkley.
In a backyard ultra, you don't race the clock. You race the last person who still believes they can outlast you.
Everyone at a backyard ultra is a DNF except one person. That's the point.
Notable Editions
Harvey Lewis Goes to 108
American Harvey Lewis completed 108 laps (723km) over 108 hours at Big's Backyard in 2023, setting a record for the event. He ran for four and a half days straight. The last person standing format meant his opponent had to quit for Lewis to win — there is no finish line to cross, only an opponent to outlast.
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Frequently Asked Questions
How long is Big Dog's Backyard Ultra? +
Big Dog's Backyard Ultra is a Last Person Standing ultra with 100m of elevation gain on trail terrain.
How hard is Big Dog's Backyard Ultra? +
Big Dog's Backyard Ultra is rated brutal with a Challenge Rating of 37/100 (Moderate). The DNF rate is 99%.
How do I enter Big Dog's Backyard Ultra? +
Must be selected based on backyard ultra performance. National team members are prioritized.. An application or essay is required. Entry costs $200. with a maximum of 75 starters.
What is the weather like at Big Dog's Backyard Ultra? +
Average temperature is 14°C (range 6°C to 22°C) with 65% humidity and a 30% chance of rain. Tennessee October — pleasant days, cool nights. Weather can be variable with occasional rain.
Are crew and pacers allowed at Big Dog's Backyard Ultra? +
Crew access is allowed. Pacers are not allowed.
What is the course record for Big Dog's Backyard Ultra? +
The men's course record is 108:00:00 set by Harvey Lewis in 2023.
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