Award Winning Obstacles

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26TH-27TH JUNE 2021


Location: Brentwood, Essex, CM15 0LA, UK
Starting:12 noon Saturday 26th June
Ending:12 noon Sunday 27th June
Distance:7km. As many laps as you can in 24 hours
Categories:Solo or Team Relay. Teams of 2-4 (Male/Female/Mixed)
Prize money:1st solo male & female completing the most laps £500. Team relay completing the most laps £1000 (to team's nominated charity)
Terrain:Muddy and trail. Water depths will not exceed 4-5'
Minimum age:17+
Prices:£160 solo. £250 per team (2-4)

OCRWC Qualifying event for Individual runners
#Charity and fundraising opportunity


The Long One

Nuclear24 is the first, brand new 24 hour obstacle ultra in the UK designed to push your limits, support each other and have fun. It will test your comfort zone, strength, stamina and mental toughness. Running Nuclear24 is a unique, once in a life-time experience on an ultra obstacle course like no other – mixed terrain above a sprawling underground Nuclear Bunker at award winning Nuclear Races.

Run as a relay team or solo, it will be a huge test just to get around; perhaps more mental than physical – there are no hard or fast rules. The natural route incorporates mud, open fields, woodland & water on every 7k lap. Expect 14 achievable man-made obstacles with limited technicality & grip strength required – examples include ziplining, sliding, carries, climbs, walls, short monkey bar style, but no rigs. There will be various alternative challenges & tasks at some obstacles…oh & we’ll look to change things round during the 24 hour time limit to keep everyone guessing.

The aim is to cross the finish line & have an incredible experience. Pushing through & helping each other overcome what seems impossible will see you through the sunset, into the sunrise & beyond.


Distance: Complete as many 7km laps as possible in 24 hours either as an individual or as a team relay. There is no minimum requirement on how many laps a team member does. Team members can do multiple back to back laps. This is your race, there is nothing stopping you running 2 laps, sleeping the night away and getting it up for further laps after a restful nights sleep and cake.. there is always room for cake.

Start/End Time: Race starts 12pm Saturday 20th June and ends 12pm Sunday 21st. All laps completed by 12pm Sunday will be counted. Course sweeper will be sent out at 12pm sharp with no further laps counting towards total.

Chip Timing: One timing chip per individual or per team. The team will use the timing chip like a relay and swap it from the completing runner to the runner about to head out on course.

A screen will be available in the Pit area to track number of laps completed.

Obstacles: There will be 28 obstacles in total with 14 open at any one point per lap. As an ultra course, there will be no grip strength dominant obstacles.

Penalties: All obstacles will have an alternative obstacle or penalty #TrustNuclear

What You Get: personalised finisher top (will be taken from your booking registration: solo – surname, team – teamname), Nuclear24 medal, hot drinks, hot showers and bragging rights

The Pits: Each runner/team will be allocated a 3mx3m pitch to set up their tent for rest and refueling in between laps. This area will become your home when you are not running. It can only be accessed by Nuclear24 runners, pit crew and marshals. Why not setup the night before to keep race day morning as chill as possible?

Pit Crew: Individual runners can have up to 2 Pit Crew members and Teams can have 1 Pit Crew member.

Camping: Free camping is available for supporters from Friday 4pm

Medics: Professional medical attendance in the event village and on course

Health and Safety: Full health and safety checks of course before and throughout

Prize Money: £500 first solo male and female completing the most full laps. £1000 (to team’s nominated charity) first team relay completing the most laps

Fundraising: There is no requirement to raise money for charity, but it’s an awesome event to use if you are looking for a challenge! To fundraise for a charity, simply set up a Just Giving page (others are also available) and get sharing your link!

OCR World Championships Qualification: Finish 10 laps to qualify for Age Category or 12 to qualify for Pro Category – easy peasy!


Working, waterproof headtorch & batteries

A sense of humour


The aim of Nuclear24 is to complete as many 7K laps as you can (or your team can) in 24 hours. Nuclear24 is accessible to all abilities – from solo runners who complete 20 laps to team or solo runners who complete 1, creating a fantastic, inclusive, and hugely supportive atmosphere where everyone is chasing their own unique goals. 

  1. Nuclear24 begins with a mass start at midday Saturday and ends midday Sunday.

  2. As a solo runner, we ask you to complete whole laps. If racing in a team, you can have as many of your team out there, however, only the person with the timing chips lap will count.

  3. Your timing chip must be worn at all times on course. For teams, the timing chip is used as a relay baton between team members by being transferred from the team member finishing their lap to the one starting their lap.

  4. You can run, walk or crawl your laps and complete as many or as few as you wish. There is no time limit on laps or minimum requirement on how many laps are completed. You can continue running for the whole 24 hours or take breaks of any length (long or short), it’s up to you.

  5. Team runners can go out in any order they choose and run as many laps as they wish. You can run single or multiple laps. There is no requirement to always have a team member on course. There is no minimum requirement on how many laps a team member completes. Run one, run all of them – the strategy is down to you and your team.

  6. If you have crossed the start line before midday on the Sunday, you can complete the lap you are on. Only full laps completed within the allotted 24hours count towards your total laps.

  7. Runners still on course after 12pm must complete their final lap by 1pm ready for the prize presentation at 1:05pm. The sweeper will head out on course at 12pm.

  8. You are required to stay until the prize presentation at 1:05pm has taken place.

  9. Any time spent off course in the pit area will be added to your lap until you next cross the start chip timing mat

  10. The Winning Solo runner (Male/Female) and team will be the ones who have completed the most amount of laps in the shortest amount of time – for teams, it could look like this:

    1. Team A 15 laps; 24:14:00

    2. Team B 15 laps; 24:30:00

    3. Team C 13 laps; 23:08:00

  11. Once the race has begun, no substitutions to your team can be made

  12. A fully  working waterproof head torch is mandatory when dark