This July we will be bringing you a special edition of the London mission as we come together to cover 80 miles for the 80th anniversary of D-Day.

The 6th June 2024 marks 80 years since D-Day, the largest seaborne invasion in history, and the beginning of the liberation of Western Europe. Many events will be taking place across the UK to mark this occasion, choose Operation Bletchley London as your event to remember those who gave so much on this momentous day. 


01 - 31 July 2024


An 80 mile challenge to deliver an encrypted message before it's too late...

Previous codebreakers will know that the London is mission is usually 50 miles but for one year only we will be covering 80- miles together as we commemorate the 80th anniversary of D-Day.

Your mission is to cover 80* miles on foot, travelling from Bletchley Park to the Churchill War Rooms in London and crack the codes as you go. With brand new codes to crack for 2024, are you up for the challenge?

Your mission starts on 1 July, and you have until midnight on 31 July to crack the codes and deliver the final message to Winston Churchill before your time runs out. 

With three levels of codes to choose from; junior, codebreaker and cypher expert, get the whole family together this summer - you have 31 days Agent. Sign up now

*If 80 miles is too little/much, you will also have the ability to adjust your challenge to suit your ability. This can be done during registration or in the 'Fitness tab' on your event page once you have signed up.

How it works

Operation Bletchley: London is a challenge event that you can take part in anywhere in the world. Here’s how it works...

  1. Sign up for just £15* and link your phone or fitness tracker to your fundraising page (you can also record your miles manually if you prefer)
  2. Start walking at your own pace (from 1 July)
  3. Receive updates and codes to crack at milestone intervals - three levels are available - Junior, Codebreaker or Cypher Expert
  4. Codes will be delivered straight to your inbox and you can select your level then
  5. Solve the codes to decipher the hidden message
  6. Complete the journey and deliver the message by the midnight on 31 July

*Also available is a £40 registration where you can opt out of fundraising.

Your mission

It's 1941 and the United Kingdom is in terrible danger. Luftwaffe bombs are raining down on towns and cities across the nation. The Royal Air Force guards the skies and the Navy protects the seas, but the threat of invasion has never been higher. German spies could destroy our telephone network at any moment, so the Home Guard is tightening up security around the capital. 

Your mission is to help us secure a new line of communication from Bletchley Park to the Cabinet War Rooms in London. We need you to walk the 80-mile route, making contact with key agents to solve puzzles along the way. Can you figure out the code and deliver the message before it’s too late? 
It is up to you how you would like to complete the walk, the challenge can be completed over a few days, or the whole month, but you need to reach the 80 miles and crack the codes before the 31st July. You can crack the codes as you go or save them up until the walk is complete. Once all the codes have been successfully decrypted you must decipher the final message and deliver it to Winston Churchill by midnight on 31st July.

Register Now

The difference your generosity can make

Operation Bletchley was created to raise money to support soldiers, veterans and their families, through the Army Benevolent Fund. There is no obligation to fundraise, but we hope you'll use your place to raise as much as possible:

£50 - could help cover travel costs so a veteran can attend a job interview.

£75 - could go towards the cost of a temporary wheelchair ramp, allowing an injured soldier to enter and leave their home.

£250 - could contribute towards the care home fees of a frail elderly veteran who requires continuous care.

£1,000 - could help pay for home adaptations so that a veteran’s young disabled child can live in a safe and accessible environment.

The Army Benevolent Fund is the Army's National Charity, here for soldiers, past and present, and their families for life.


Sponsor a friend

Find the fundraising page of someone already taking part in Operation Bletchley.