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 
  • April – Paris – 100 miles - LIVE NOW!
  • July – London – 50 miles
  • October – Cairo – 30 miles


From 1st April, take on our Paris mission, challenge yourself and your family and friends to cover 100 miles*.

You’ve been dispatched behind enemy lines in France and must successfully deliver the encrypted message to a secret agent waiting for you in the heart of Paris. Do you have what it takes to accomplish your mission and deliver the final message before time runs out?

*If 100 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 April.


It's 1942 and the situation in France is at boiling point. The Nazi occupation has cut us off from our agents on the ground, so we need you to go behind enemy lines to make contact. We cannot afford for our intel to be compromised, so you must move through the shadows and crack codes along the way to avoid detection. This mission is not for the faint hearted. Your success is critical. Do you have what it takes?

Sponsor a friend

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