Take on Operation Bletchley. Your codebreaking challenge. 

Operation Bletchley is a series of codebreaking challenges taking place four times a year for the Army Benevolent Fund, complete all 4 in one year and be suitably rewarded!

Take on one of the UK's most innovative events as you tackle the fiendish codes, explore the great outdoors and learn more about our incredible heroes from the Second World War. Your mission is to cover the miles, crack the codes and uncover the secret message you need to deliver to Winston Churchill before time runs out. 

1 mission | 10 codes | 1 month - can you complete them all?
  • Jan – Berlin – 40 miles - LIVE NOW!
  • April – Paris – 100 miles
  • July – London – 50 miles
  • October – Cairo – 30 miles


From 1st January, take on our Berlin mission, challenge yourself and your family and friends to cover 40 miles* on foot through Soviet territory, decrypt vital intelligence about the blockade, cracking codes as you go and help bring our stranded contacts back to HQ. Do you have what it takes to accomplish your mission and deliver the final message before time runs out?

*If 40 miles is too much/too little, you will also have the option to increase/decrease it before the mission start date to suit your ability.

Test your codebreaking skills as you conquer one of our epic challenges. Immerse yourself in the incredible stories of some of the bravest people who helped us triumph against our foes. Can you crack the final code before time runs out?

You can take part from anywhere in the world using your phone, fitness tracker or a good old map. 


Choose from one of three difficulty levels - junior, codebreaker or cypher expert. Don't be fooled into thinking the junior level is too easy!

Be a part of something incredible this winter whilst supporting soldiers, veterans and their families. 

You have one month to cover the miles, crack the codes and deliver the final secret message.

REGISTER NOW - Your mission starts on the 1st January.


It’s January 1949. Since the fall of the Nazi regime, Germany has been carved up into four zones. Deep inside the Soviet zone, hundreds of miles from the Western boundary, is the capital of Berlin. And like the rest of the country, Berlin, too, is divided into four zones.

Cooperation between East and West has deteriorated, and on 18 June 1948, Stalin’s communist regime closed road, rail and water supplies to West Berlin – leaving two million Germans cut off from vital resources. 

We need you to go beyond the blockade and discover the truth of what’s happening in the East. We’ve arranged for you to make contact with key officials, but you’ll need to move on foot and crack codes along the way to avoid being captured. It’s a frosty journey that’s certainly not for the faint-hearted. Are you up to the challenge?

Sponsor a friend

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