William and Kate celebrated St Patrick's Day with the Irish Guards.

The couple wished their followers a happy St Patrick's Day on Twitter.

They joined the Irish Guards for the St Patrick's Day parade and visited Mons Barracks.

Kate took the salute as Colonel of the Irish Guards.

This was her first time taking the salute for the Irish Guards.

William watched from the wings as the outgoing Colonel.

The event was historic for the royal couple.

There were earlier reports of Kate preparing for a special event.

The couple's Twitter message suggested they were excited for the celebration.