Rat Race 100 ultramarathon
Edinburgh Castle to Glamis Castle
The Rat Race 100 Series is the UK’s most inclusive and accessible 100-mile ultramarathon series, built for people who never thought they could complete a 100 miler. Whether you choose to run, walk or mix the two, our three fully supported 100-mile endurance events are designed to help everyday adventurers achieve an extraordinary bucket-list finish line. With no qualifying times, walker-friendly cut-offs, fully waymarked routes, stocked pit stops and unmatched on-course support, this is ultra running without barriers.
Journey between some of the UK’s most iconic castles and historic landscapes as each event delivers a spectacular point-to-point adventure packed with unforgettable scenery and inspiring finish lines.
2026 Info
Dates 25 - 27 July 2026
Duration 48 hours
Distance 100 miles (160km)
Discipline Event Discipline - Run/Trek
Event Type Mass Participation Events
Highlights
Earn your Trilogy buckle if you do all 3
The Rat Race 100 is a unique three-part 100-mile ultramarathon series where each edition picks up exactly where the last one finished, creating an epic continuous journey. Complete all three over three years, or tackle them all in a single year if you’re feeling ambitious, to earn the prestigious Rat Race Trilogy Finisher buckle.
No barriers to entry With no qualifying times needed, a walker friendly 2.5mph completion pace, fully waymarked routes, fully supported in event logistics and fully stocked pit stops. The Rat Race team are here to help you go the distance and support you to this bucket list finish line, no matter your pace or background.
Highest completion rate in the UK In our inaugural 100 miler we’re proud to have achieved the highest completion rate for this distance in the UK. 65% of the field claimed this glorious medal at the foot of Edinburgh castle. We're looking to beat that in 2026!
Generous completion window
We believe in making big adventures accessible. That’s why this route is waymarked, fully supported, and set at a pace that allows everyone to take part. There are no strict cut-offs and you have 48 hours to cross the finish line.
Itinerary
Friday: Registration Day The adventure begins! You will need to attend Registration on Friday in Edinburgh city to centre to complete tracker collection. Registration is open from 1200 - 2000.
Saturday: Rat Race 100 begins
It's time to run or walk 100 miles!
Bag drop opens at 0630 on King Stables Road.
The start is at 0800 at Princes Street Gardens, please follow our signage to get to the start.
Sunday: Keep going Rat Racers!
Our course is open until 0800 on Monday morning and hundred of Rat Racers will be making their way towards Glamis Castle!
Monday: Rat Race 100 finishes
We will welcome our incredible final Rat Racers over the line in the morning and celebrate everyone's amazing achievements over the weekend!
Your Adventure Leader
Seb
Seb brings extensive experience delivering complex mass participation events and remote adventure experiences in challenging environments around the world. A climber, splitboarder, mountaineer and trail runner, he’s happiest exploring wild places. Inspired by big mountains, remote landscapes and true adventure, Seb combines real expedition experience with calm, expert project delivery to create adventures that feel both challenging and brilliantly executed.
What's Included
Follow the orange arrows
Fully Waymarked
The Rat Race 100 is fully waymarked, making it accessible and beginner friendly. You will si
