The new Lord Warden of the Cinque Ports has been installed at a ceremony at Dover Castle in Kent.
Admiral Lord Boyce spent more than 40 years in the UK armed forces
Admiral the Lord Boyce is officially taking up the historic ceremonial role three years after the death of the last Lord Warden, the Queen Mother.
He said he is "only too conscious of the honour" of being asked to take up the post.
The Lord Warden is a figurehead for the Cinque Ports towns of Hastings, Romney, Hythe, Dover and Sandwich.
The Cinque Ports in Kent and Sussex were responsible for defending England from invasion across the Channel in medieval times and the role of Lord Warden has existed since the 13th Century.
The Crown granted the towns special status in recognition of their local seafarers and fishermen defending and policing the coastline.
The 161st Lord Warden touches the key to Dover Castle
The Queen Mother held the role from 1978 until her death in 2002.
Admiral the Lord Boyce, a former head of the UK's armed forces, was announced as her successor last July.
Previous holders of the post include King Henry VIII and Sir Winston Churchill.
The new, and 161st, Lord Warden said of his predecessors: "Such people as William Pitt or Winston Churchill or the Queen Mother, I mean these were extraordinary people in extraordinary times and I just feel it's very humbling."
There was a 19-gun salute from HMS Albion in Dover and an event on board the ship on Tuesday evening to welcome him into the role.