Topic summary
Portsmouth Harbour

50°49′24.60″N1°7′22.08″W / 50.8235000°N 1.1228000°W
Portsmouth Harbour is a large natural harbour between Portsmouth and Gosport in Hampshire, England, covering an area of 12.6 km (4.9 sq mi). It is a biological Site of Special Scientific Interest, a Ramsar site and a Special Protection Area.
The harbour's mouth opens into the Solent. Geographically, the harbour is a ria: formerly it was the valley of a stream flowing from Portsdown into the Solent. At its north end is Portchester Castle, of Roman origin and the first fortress built to protect the harbour.
The harbour is best known as the home of the Royal Navy, HMNB Portsmouth. Because of its strategic location on the south coast of England, protected by the natural defence of the Isle of Wight, it has since the Middle Ages been the home to England's (and later Britain's) navy. The narrow entrance, and the forts surrounding it gave it a considerable advantage of being virtually impregnable to attack from the sea. Before the fortifications were built the French burned Portsmouth in 1338. During the civil war parliamentary forces were able to carry out a successful within the harbour and capture the six-gunned Henrietta Marie.
In modern times, the harbour has become a major commercial ferry port, with regular services to Bilbao, Santander, Caen, Cherbourg, St Malo, Le Havre, The Channel Islands and the Isle of Wight. There is also a passenger ferry to Gosport. The international ferry port also saw a cruise terminal expansion in 2012 and sees regular cruise ship operations. It is also a major area for leisure sailing. In 2001 the Gunwharf Quays development, was opened on the site of HMS Vernon (a former naval shore establishment).