Camille Herron Sets 48-Hour Running World Record of 435.336 kilometers (270.505 miles)

Camille Herron sets the women’s 48-hour world record at the 2023 Sri Chinmoy 48 Hour Festival in Australia.

By on March 25, 2023 | Comments

Over the last two days, ultrarunning history was made in Australia. The U.S.’s Camille Herron set the 48-hour running world record at the 2023 Sri Chinmoy 48 Hour Festival, which was run in Bruce, Australia. Her official distance is 435.336 kilometers (270.505 miles).

The previous record of 411.458 kilometers (255.668 miles) was only set last month, in February 2023, by the U.K.’s Jo Zakrzewski at the 2023 Taipei Ultramarathon.

Herron’s performance sets a new 48-hour standard by over 23 kilometers (about 14 miles).

Camille Herron - 48 hour world record - 2023 Sri Chinmoy 48 Hour Festival - photo 1

Camille Herron en route to the 48-hour world record at the 2023 Sri Chinmoy 48 Hour Festival in Australia. Photo: Sri Chinmoy 48 Hour Festival

The race’s timing system and social media reports together indicate Herron completed the first 100 kilometers (62 miles) in about 8 hours, 50 minutes.

She then hit the 100-mile (161 kilometers) mark with about 14 hours, 41 minutes on the race clock.

Next, at 24 hours or halfway, she’d run more than 238 kilometers (148.5 miles).

The 200-mile (322 kilometers) mark came and went with 33 hours, 35 minutes on the clock.

She surpassed the prior world record of 411.458 kilometers (255.668 miles) at about 45 hours, 8 minutes elapsed.

She took a 40-minute break at the halfway point, plus several more eight- to 10-minute breaks along the way.

Camille Herron - 48 hour world record - 2023 Sri Chinmoy 48 Hour Festival - with Robert de Castella

Camille Herron with Australian Olympic distance runner Robert de Castella before the start of the 2023 Sri Chinmoy 48 Hour Festival in Australia. Photo: Sri Chinmoy 48 Hour Festival

The women’s 48-hour record has seen much progress in the last year. In addition to Herron’s record this weekend and Zakrzewski’s 411.458 kilometers (255.668 miles) last month, the latter of which is still so fresh it’s not ratified, Poland’s Patrycja Bereznowska set a record of 403.32 kilometers (250.611 miles) in May 2022 at the UltraPark Weekend 48 Hour in her home country.

For a bit of fun context, in setting the women’s 48-hour world record, Herron bested both the women’s and men’s U.S. records. Marisa Lizak set the previous 48-hour U.S. women’s record with  391.87 kilometers (243.5 miles) in 2020. The men’s U.S. record of 421.9395 kilometers (262.1811 miles) was set in 2017 by Olivier Leblond.

With this performance, Herron continues to cement her place in the history of ultrarunning. She is already the current world record holder for 50 miles, 100 miles, and 24 hours.

As with all such records, the official distance and result are unofficial pending ratification by world governing bodies.

Full results from the 2023 Sri Chinmoy 48 Hour Festival.

Camille Herron - 48 hour world record - 2023 Sri Chinmoy 48 Hour Festival - photo 2

Camille Herron en route to the 48-hour world record at the 2023 Sri Chinmoy 48 Hour Festival in Australia. Photo: Sri Chinmoy 48 Hour Festival

Meghan Hicks

Meghan Hicks is the Editor-in-Chief of iRunFar. She’s been running since she was 13 years old, and writing and editing about the sport for around 15 years. She served as iRunFar’s Managing Editor from 2013 through mid-2023, when she stepped into the role of Editor-in-Chief. Aside from iRunFar, Meghan has worked in communications and education in several of America’s national parks, was a contributing editor for Trail Runner magazine, and served as a columnist at Marathon & Beyond. She’s the co-author of Where the Road Ends: A Guide to Trail Running with Bryon Powell. She won the 2013 Marathon des Sables, finished on the podium of the Hardrock 100 Mile in 2021, and has previously set fastest known times on the Nolan’s 14 mountain running route in 2016 and 2020. Based part-time in Moab, Utah and Silverton, Colorado, Meghan also enjoys reading, biking, backpacking, and watching sunsets.