Gransden Mystery Marathon

In 2020, we introduced a new event to co-incide with the regular Gransden Muddy Fun Run:

“The Gransden Mystery Marathon”

This ‘race’ pays homage to the original GORM (Gransden Off-Road Marathon) and other ‘notorious’ events like The Barkley Marathons (Google it, or search out the excellent Netflix documentary!).

Read a blog post about the 2020 Mystery Marathon

2021 Event – Sunday 31st January 2021


We are planning to host the Mystery Marathon again in 2021, future lockdowns & Covid guidelines permitting! In order to keep our event safe, runners (or small groups of runners, as rules allow) will be allocated an individual start time. There will be no congregating at the start or finish permitted, and timing will be manual. Our checkpoints will be equipped with sanitiser. We will of course have a brand new route for you to navigate!

What to expect?

Given the challenging terrain and time of year, this is probably a race for more seasoned distance runners (see entry details below). You will run a full marathon course, predominantly off-road, in the local countryside.

Start time will be allocated from 8:00am (earlier starts can be accommodated if necessary)

The route will be a loop, mostly off-road, with a number of unmanned checkpoints. You will receive information about the route on the day of the event only. At each checkpoint you will pick up a map to guide you to the next checkpoint.

The course will not be marshalled or supported in any way and therefore entrants must take full responsibility for their safety during the event. You should carry supplies (water and food) as well as a phone for emergencies. We will also use the app what3words to help locate HQ and the various checkpoints.

Sadly we can’t provide any cakes or refreshments at the finish, so we suggest you bring something yourself. Likewise we can not promise any award ceremony or prizes this year, we hope you understand; the satisfaction of completing the route without getting lost will be sufficient!


The course will be challenging, and given the time of year, potentially impacted by the weather. As a result, numbers will be limited and entry will be by application. Please contact the organiser giving details of ‘qualifying’ race experience. You will be asked to complete a registration form to confirm your place.

Entries open – please contact race director via the contact page

There is no set entry fee, however, we would expect you to make a suitable voluntary donation to our school fundraising effort.