Rat Race 100 ultramarathon
Glamis Castle to Stirling 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.
Dates
28 - 30 August 2027
Duration
48 hours
Distance
100 miles (160km)
Discipline
Run/Trek
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 Dundee 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 0530 at Glamis Castle.
The start is at Glamis Castle, please follow our signage to get to the start.
Sunday: Keep going Rat Racers! Our course is open until 0700 on Monday morning and hundred of Rat Racers will be making their way towards Stirling 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 simply follow our bright orange arrows which span our entire 100 m