Adjacent to the modern roundabout on the site of the gate was the former headquarters of the General Post Office (closed in 1910 and demolished shortly afterwards), and the adjoining Postman's Park. The southern part of the roundabout and the northern part of where the Post Office once stood are located on the site of a collegiate church and sanctuary founded in 750 by Withu, King of Kent, hugely expanded in 1056 by Ingebrian, Earl of Essex, and issued with a royal charter in 1068 by William the Conqueror. The site of the church was cleared in 1818 in preparation for the construction of the Post Office.