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Chiltern 50 Ultra Challenge 2025

This 50km looped route covers some of the best of the Chilterns countryside. You can Walk, Jog, or Run along historic trails and over rolling hills at the Chiltern 50 Ultra.

A challenge event you can take on at your pace. The Chiltern 50 Challenge invites you to walk, jog or run a distance of your choice, along a signed route, with free food and drink at regular rest stops, plus support including medics, marshals and massage. Get the ‘Ultra Challenge’ support & hospitality all the way – helping you to push yourself further and achieve something really special for The Brain Tumour Charity.

This 50km looped route covers some of the best of the Chilterns countryside. You can Walk, Jog, or Run along historic trails and over rolling hills. Starting & finishing at a Base Camp in Henley Showground, there’s a Saturday night celebration BBQ & entertainment with camping options. Passing through nature reserves, forests, and a few hills with great views – it’s a route with real variety, and some wonderful scenery – and it’s all easily accessible from London. With 25km and 10km challenge options also available – there’s a challenge here for everyone – and you can join as an individual or as a team of friends / family.

You may have to dig deep at times, you’ll meet new friends along the way, and the journey will be unforgettable! As you cross the finish line, you’ll get a big welcome from the cheer squad, a glass of fizz, t-shirt, and a special medal to celebrate your achievement.

What you’ll get:

  • ✓ Sign up from £10
  • ✓ Inclusive & fun event with a great atmosphere and camaraderie
  • ✓ Choose your distance – 10km, 25km, or 50km options
  • ✓ Walk, jog, or run – it’s your challenge, your way!
  • ✓ A fully signed route, with a team of ‘Trekmasters’ out on the trail with you
  • ✓ Regular covered rest stops, with free food & drink, massages and medics
  • ✓ An epic finish line moment, with a glass of fizz, medal and t-shirt
  • ✓ Camping, transfer and parking options to make getting there & away easy
  • ✓ Full fundraising support, and a choice of fundraising options

As The Brain Tumour Charity are an official partner on this event, you get a 25% discount on the ‘Full Sponsorship’ registration fee when signing up to support us.

Winter Deal!

Get an extra 25% off on ‘full charity sponsorship’ options! Offer ends December 1st. For full details on how to redeem this offer, simply follow the link to sign up.

  • *Excludes 10km/10 mile events

Click below for full details of prices and to sign up:


Fundraising options:

Full Charity Sponsorship

You pay a small registration fee, do lots of fundraising and we cover the cost of your event place! As we are an official Charity Partner – you get 25% off the standard reg fee below

DistanceReg FeeFundraising target
50km Challenge£40£375
25km Challenge£30£275
10km Challenge£20£100

Mixed Funding

Pay half of the event place cost yourself, fundraise a bit less and we pay the balance of the event place cost.

DistanceReg FeeFundraising target
50km Challenge£75£225
25km Challenge£50£150
10km Challenge£22.50£70

Self Funding

You pay the full cost of the event place – fundraise whatever you want, with no set target or deadline, and there’s no cost at all to the charity!

DistanceReg Fee
50km Challenge£139
25km Challenge£89
10km Challenge£39

Click below for full details of prices and to sign up:


Important information from the event organiser

All sponsorship goes directly to the Charity via your online fundraising page. At least 50% of the sponsorship target should be with the Charity 3 week prior to the Challenge. At this time, the Charity agrees to pay a fee for your place to the Organiser (similar to the Self Funding cost – or half of it for Mixed Funding as you’ve already covered half). Failure to meet the deadline may result in cancellation of your place by the charity. The remaining 50% and any extra, should be with your Charity by 4 weeks after the Challenge.

This event is organised by Action Challenge.

If you have any questions, don’t hesitate to get in touch with the events team events@thebraintumourcharity.org or call 01252 237867.


Event details

When: Saturday 27 September 2025

Where: Chiltern Hills

Registration fee: £20 – £139

Get a 25% discount on the ‘Full Sponsorship’ registration fee when signing up to support us!

Fundraising: £70 – £375

Type: Walk, Jog or Run

Distance: 50km loop, 25km & 10km options

Supporting you

You’ll receive support from the Challenge Events Team including: