Her Majesty The Queen has helped the Corps of Royal Engineers to mark a major milestone.
She visited the British Army sappers at Brompton Barracks in Kent on their 300th anniversary.
The Royal Engineers trace their origins back to the military engineers brought to England by William the Conqueror, although the Corps itself wasn't established in 1716.
Gibraltar is often thought of as the spiritual home of the Corps and it was there that the first company of soldier sappers came into being.
One of their major contributions to history was the creation of the intricate tunnel system within the Rock itself