Gibraltar: The British Rock

A ready-made geological fortress, the Rock is about 1,400 feet high, three miIes long, and three-quarters of a mile wide on average, rising sheer at the north end and tapering to a cliffed plateau at the south. The eastern side rears up like the walls of a castle, while the few weak points on the more gently sloping western side, where the city stands, have been fortified over the centuries In addition its pale porous limestone is riddled with almost thirty-five miles of manmade tunnels and chambers, some dating from the Great Siege, but the majority from the Second World War and intended to quarter a garrison under threat of the German assault that never was – Operation Felix .