Jestyn Reginald Austin Plantagenet Philipps, 2nd Viscount Saint Davids, 1917-91, educated at Eton and Cambridge, founded a pirate club in the 1960 based on a narrow boat near Camden Lock to give children the chance to muck about in boats.
 
They became pirates in more than name, making raids on passing boats to raise funds for their charity and holding the Lord Mayor of London to ransom in their club dungeon. Their founder gained the more manageable pirate name of 'Peg-Leg' following an accident when he fell between the boat and its mooring.
 
Architect Richard Seifert took time off from his less desirable intrusions into the London skyline - Centre Point, the NatWest tower, the Tolworth Tower etc - to design the club its Pirate Castle, built in 1977. It still looks much like it did, though it was extended in 2008 by AAB Architects, providing greater disabled access.