About the 2026 Ultra X Spring Trail Series
Ultra X brings you epic multi-day ultramarathons in some of the world’s most breathtaking locations - It's more than just a race, it's a journey. Push your limits to the test, join a supportive community and experience the adventure of a lifetime - The finish line is just the beginning, this is the UltraXperience!
The Spring Trail Series takes place on the Serpent Trail, a stunning route that weaves through the greensand hills, rivers, woodland, and lowland heath of the South Downs National Park.
How to get started
- Choose a distance that suits you: From 12km to an epic 110km.
- Pick a fundraising option: You'll need to reach a minimum fundraising target based on what you choose.
- Sign up on the Ultra X website: By taking part in support of CALM you’ll get 50% off your reg fee.
How we'll support you
Whether it’s your first time taking on an Ultra Challenge or you’re back for more, we’re here to make sure you have the best time. As part of Team CALM you’ll receive:
A CALM t-shirt or vest so you look the part on the day
Dedicated support from the Challenge Events team
Access to the CALM Running Facebook group
Tips and advice to help you smash your fundraising target
Got a question?
Check out our FAQs or head to the Ultra X website. If you can’t find an answer there, get in touch and we’ll be happy to help.
