Walmer Castle is one of a trio of artillery forts built along the Kent coast by King Henry VIII in 1539-40. Since 1708, it has been the official residence of the Lord Warden of the Cinque Ports. The Lord Warden was once one of the most powerful officials in the Kingdom, responsible for defence of the Kent and Sussex coastline from invasion. Notable holders of the position include several Prime Ministers, such as William Pitt the Younger, The Duke of Wellington, Lord Palmerston and Winston Churchill.