Prince William and Kate Middleton, now the Duke and Duchess of Cambridge, honored the Irish Guards for their service in Afghanistan during a ceremony at Windsor Castle.

Kate wore a military style dress with an Irish shamrock pinned to her lapel.

Prince William was married in the uniform of the Irish Guards and is their Colonel in Chief.

It will be the first time the royal couple have visited the regiment since they were married.

The 1st Battalion of Irish Guards returned from a six month tour of duty in Afghanistan in April.

William presented the families of three fallen members with the Elizabeth Cross.

The guards were formed in 1900 in recognition of the actions of Irish regiments in the Boer War.

The unit is heavily involved in ceremonial duties in Britain, but it has also been prominent in the fighting in Afghanistan.