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XNRG 2022 events now open for booking!

This event is scheduled to go ahead, with some differences. Read our Covid-19 policy

No. of days 1 day

Distance 31 mi

Ascent gain 695 m

Accom. no

Food no

A one-day, 50km ultra raising funds for a great cause. Choose to pay for your place upfront, or bag a FREE spot if you commit to fundraise. All funds will go to Humanity Direct, a charity changing the lives of children needing medical care in developing countries.

Latest results


  • Free parking at Dr Challoner's Grammar School
  • A fully recced and marked route to make the event special and challenging for all
  • Full medical cover throughout
  • A quality finisher's technical t-shirt and medal
  • Toilets, showers and changing facilities
  • Checkpoint food and water throughout
  • Free tea, coffee and cake at the finish
  • Prizes and trophies for overall and category winners
  • A great atmosphere and a fun, but challenging, day out
  • Action photos, free to download after the event

The winners, runners up and age group winners will receive fantastic prizes or vouchers from our sponsors.

Also, win a weekend's free car rental with Imperial Vehicles - see below in 'More information' for details.



Registration opens.


Rolling start begins.


Walkers start.


Walk/run start.


Run/walk start.


Elite runners mini mass start.


Massage and refreshments available.


Prize giving or when enough runners have finished.


Standard entry




The £58 entry fee will be donated to fund a vital operation, or alternatively enter for FREE, if you commit to raise funds for Humanity Direct.

If you're fundraising book now through our system, then visit Humanity Direct's website to register yourself.

Please note: a 2.5% service charge, levied by the registration software, will be added to your total. We are using a new entry system that takes payment through the secure system Stripe. No payment information is retained by Extreme Energy, or our entry system tool.

Email us on if you have any questions about your options.

If for some reason you are not able to make the event you have entered. The XNRG refund policy is that we will give you 70% refund of your entry fee up to 1 month before the start date of the event. You also have the option (1 month before the date of the event) to get a 100% transfer credit to another one of the other Humanity Direct 1 day events, or you can donate your entry fee to the charity. All entry fee money goes directly to the charity and directly to helping children with life changing operations. These options you can execute on your Ultrabritain entry page.

After this time we are sorry there will be no refunds or transfers to future events. Refunds will be to your booking credit card.

Race-day Preparation

Kit List

The only compulsory kit is a fully charged mobile phone and a minimum 500ml of water, but it's worth taking a look at our recommended kit list.

Other equipment may be made compulsory by the race director depending on the weather.


The event is supported by our course manager and his experienced on-course crew to ensure you have a great event. A fully qualified medical crew will also be there to give first aid and manage any serious medical problems in cooperation with the emergency services. We strongly recommend taking a moment to read our medical page before booking.


We've answered a range of common questions in our FAQ. For other questions, say hello on

Download race details

More Information

Join us for the first in our XNRG charity single-day series for 2022. Within a stone's throw of London, you'll race across the glorious Chilterns - all fully supported and with bags of XNRG encouragement and atmosphere. It's ideal for anyone wanting to 'step up' to covering an ultra distance, as well as being great training for multi-stage events. And it's all for a good cause.

We recommend a donation of £58 when you sign up, or you can pledge to raise as much as you can instead of paying to enter - saving and changing the lives of children in developing countries who desperately need surgery.

how it works

It's simple. The entry fee is donated to Humanity Direct, OR, if you prefer, you can enter for FREE and start a fundraising page instead to raise as much as you can (minimum donation: £58). 100% of donations go towards children's operations and medical care in developing countries through Humanity Direct.

Why we do it

In 2019, Humanity Direct raised £24,000 through the three XNRG Humanity Direct Ultras, funding life-saving and life-changing operations for 35 children. We're hoping to raise even more in 2022!

“The support we’ve had from XNRG has been phenomenal. Thanks to you we’ve rolled out a vital eye-testing programme for children in rural Uganda with over 600 children receiving free glasses so far. Your donations and dedication have also helped us continue to provide life-saving and life-changing surgery for children whose families are live on less than a $1 a day and who would never be able to afford the medical care they need.  XNRG ultras truly do change lives!"

- Nick Swift, Humanity Direct’s Founder



Entries will close one week before the event (or when full). A waitlist option will be available if the event becomes fully booked.

Navigation and Support

Starting and finishing at Dr Challoner's Grammar School, Amersham, the 50km route takes in many areas of natural beauty, including the Misbourne Valley and the Chess Valley - some of the best spots in the Chiltern Hills. The route mainly follows footpaths and bridleways, with a little road section, all marked comprehensively with tape, paint and direction arrows. All competitors will also be given a map and GPS download. The event is supported by our course manager and his experienced on-course crew to ensure you have a great event. A fully qualified medical crew will also be there to give first aid and manage any serious medical problems in cooperation with the emergency services.

Aid stations

There will be four checkpoints at regular intervals, fully stocked with water, and sweet and savoury food to keep you fuelled.

Due to the risk of cross-contamination, we can't provide checkpoint food to suit all dietary requirements. If you require special food or snacks to suit any allergies or vegetarian/vegan diets, please bring your own. Put them in containers, marked with your name and checkpoint number and give them to the checkpoint teams at the start of the race.

Win a weekend's free car rental with Imperial Vehicles

Our friends at Imperial Vehicles are offering all Amersham Ultra entrants the chance to win a weekend's FREE rental on the vehicle of your choice.

All you have to do to take part is to leave your contact details with the team on race day, giving them permission to send you offers and news.

At the end of the ultra, we'll choose a winner at random. The prize includes:

  • Fully comp insurance (£1,000 excess applies)
  • Unlimited mileage
  • Delivery and collection
  • Breakdown cover.

Have a hen / stag weekend coming up? Need a bus? Have a house move? Need a car? It could be yours for FREE!

To enter, you must:

  • Have a full UK clean driving license
  • Be over 25, with at least two years of driving experience
  • Be planning to use the vehicle within the UK only
  • Hold the category license for the vehicle of your choice.

See you on race day!

- The Imperial Vehicles team


Trees Not Tees

As part of your entry fee you will get an event T-shirt, or you can choose not to have the T-shirt and the money we would pay for the T-shirt will go to Trees not Tees and a tree will be planted instead.

For more details visit their website -

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A big thank you to everyone at XNRG and Humanity direct for a wonderful day yesterday, you even sorted the weather!! It was a beautiful route and really well organised and signed. Thanks to all the volunteers and everyone who made it possible.

I just wanted to say how much I enjoyed my first ultra on Saturday! Wasn’t quite prepared for the mud... but at least the weather was lovely! I particularly enjoyed how kind and supportive everybody was, and the great spirit everybody had throughout the whole day.

A big thank you for another great event.
Great organising, great support, fab checkpoints with picnics, love the course (if a bit muddy).
I love the atmosphere of your events, both the participants, crew and supporters.

We can't wait to see you there! Questions? Say hello on

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