Big’s Backyard Ultra World Championship 2025: Start time, format and how to watch Laz Lake’s other fiendish creation

It’s one of the craziest World Championships around and it takes place – or, more accurately, it starts – this week in Bell Buckle, Tennessee.

The Big’s Backyard Ultra was created by Lazarus Lake – the genius behind the Barkley Marathons – and named in honour of his beloved dog.

RELATED CONTENT: Laz Lake tells us why Big’s is the world’s toughest but most sociable race

It will feature 75 of the world’s best ultrarunners completing 4.167-miles on the hour, every hour, on a testing course in Tennessee until there is just one person left standing.

Read on to find out more about what has become a global phenomenon…

Date, start time and how to watch live

It starts at 7am Tennessee time on Saturday 18 October, just a few minutes after sunrise.

That corresponds to 13:00 in the UK, 14:00 in Europe, 08:00 on the East Coast and 05:00 on the West Coast.

The location is Laz’s ‘backyard’ in Bell Buckle.

RELATED CONTENT: RUN247 meets the legendary Laz Lake

And you can watch it unfold live here – we’ll add the embed below when it’s up and running.

We’re promised a dedicated commentary team for first time, interviews and updates every six hours.

How to qualify and who’s racing

The top 50 winners of the national championships [which were held concurrently last year at the World Team Championships] secure berths at the World Individual Championships.

In addition to those champions, there are an additional 25 runners selected from what’s called an ‘At-Large list’ – the top performances of the previous two-year qualifying period (August 16, 2023 to August 15, 2025).

Aussie Phil Gore and New Zealander Sam Harvey will surely be the favourites after they pushed the format to new heights at the Dead Cow Gully Backyard Ultra in June this year – Gore was last person standing with 119 yards (just an hour short of five days!), with Harvey getting the assist in 118.

Numerically Poland’s Lukasz Wrobel only has Gore and Harvey ahead of him after his 116 yards earlier this year.

But Belgium, with the likes of Ivo Steyaert and Merijn Geerts, have a formidable contingent – and remember they won the team competition last year, which is held every two years.

And legendary American schoolteacher Harvey Lewis – more about him below in the previous winners section – is another to keep a close eye on.

There are just four women who have qualified, including the UK’s Sarah Perry who set a national record with 59 yards in October last year.

Meg Eckert holds the women’s world record of 87 laps from this event last year when she bagged the assist to Scott Snell – both of them are back for more this week.

The full roster for 2025 is here.

Format

A backyard ultra is a “last person standing” ultramarathon where runners must complete a 4.167-mile (6.7 km) loop on the hour, every hour. That is called a ‘yard’.

They are eliminated if they cannot finish the loop within the 60-minute time limit or are not back on the start line / start pen for the next loop.

The race continues until only one runner remains to be crowned the winner, who must complete one final lap alone. The second-last runner is given the credit for the “assist”.

The reason for the 4.167-mile length is that 24 hours equates to exactly 100 miles. So Gore’s record 119 yards was just 4.167 miles short of 500.

So clearly it’s an incredible physical test, but also a daunting mental one given that runners have the opportunity to ‘quit’ every hour.

It’s a format that has spawned more than 500 other similar races around the world in 85 different countries.

The weather looks favourable this year and when we here at RUN247 spoke to Laz himself last month, he was confident the world record would be beaten!

RELATED CONTENT: We review the first ever authorised Laz Lake biography

History

Laz calls it “sudden death overtime” every loop and who better to write about how this event has grown so rapidly.

Here’s what he posted on Facebook this week, in his own inimitable style:

“two years in the making,
the big’s backyard world championship is almost here.
saturday they will be speaking 30 languages in my yard.
the best of the best
the elite of the sport of backyard
will meet on the site of the very first backyard,
where a short 15 years ago a few dozen athletes met to play with a new format…
.
no one dreamed where that little gathering would lead.
that 15 years later
tens of thousands of backyarders would be playing
in backyards in 85 countries around the world.
85, and counting.”

Recent winners and world records

Some of ultrarunning’s biggest names are on the roll of honour.

Unlike Laz’s other famous creation, it didn’t take long for a woman to emerge triumphant – Maggie Guterl the first to do so in 2019.

The GOAT Courtney Dauwalter was credited with the “assist” the year before and she would be the last person standing in 2020.

Arguably the greatest race so far came in 2023 when Ihor Verys pushed Harvey Lewis to a then new world record of 108 yards.

The following year Verys would go on to finish the fearsome Barkley Marathons at his very first attempt.