Big Bertha 12-hour Endurance Run: 21/8/27
10km laps, 12 hours, beautiful trails around Bertha Loch. How many laps can you complete in 12 hours?
Challenge Yourself
Big Bertha is a 10km loop around Bertha Loch – do as many as you can in 12-hours. Take part solo or as a team!
Chip Timing
Chip Timing provided by Keep it Simple Timing Services.
Water Station on the course
Water at approx 5km
Insurance for all participants
Insurance is included (or deducted if you have your own)
Results in real Time
Get your results on the day as you cross the finish line!
Online Entry
Enter online!
prizes for Furthest distance
Prizes for F/M and NB winners
Fully Marked and Marshalled Route
The trail is an easy to follow marked route
Medic Team
Our team of medics will make sure you’re safe.
Exciting Trails!
The trails around Bertha Loch and Almondbank are exciting and varied!
Medals for Every Finisher
Lovely medal created by The Workshop Aberfeldy
parking Available
Free all-day parking while you enjoy the challenge
Refreshments available at the finish
Refreshments provided at the finish by Starfish Cakes and Bakery
Your Choice! How far can you go?
12-Hour event
Team or solo Challenge
Ultra Running
Photos from Big Bertha 2026
The third Big Bertha 12-hour Endurance Event took place on Saturday 22nd August 2026
Photos from Big Bertha 2025
The second Big Bertha 12-hour Endurance Event took place on Saturday 30th August 2025
Photos from Big Bertha 2024
The first ever Big Bertha 12-hour Endurance Event took place on Saturday 31st August 2024
Register for Big Bertha 12-hour Trail Run
Join the 12-hour challenge now!
Experience the thrill of running on beautiful 10km trails for 12 hours straight. Are you ready to push your limits?
Experience the thrill of trail running!
Gather your friends and conquer the trails together as a team. Share the joy, the sweat, and the victory at Big Bertha Trail Run!
tHE ROUTE
2026 – Results
2025 – Results
Big Bertha 26 Results
Overall Podium
Jamie Briggs- 9 Laps
Sharon Law – 9 Laps
Hamish Munro – 9 Laps
Female Podium
Sharon Law – 9 Laps
Zara McKenzie – 8 Laps
Tamara Janssen- 7 Laps
Male Podium Jamie Briggs – 9 Laps Hamish Munro – 9 Laps Jamie Gordon – 9 Laps
By the Numbers
• 27 starters,
• 162 total laps completed by the field
WE RUN EVENTS YOU LOVE TO RUN
ABOUT US
Wee Run events is a community interest company dedicated to providing fun and challenging events of different types and distances.
We are a not for profit company based in the central belt of Scotland.
We have over 40 years of event experience.