A conference in Havana marking the 40th anniversary of the Cuban missile crisis has ended with a visit by participants to sites related to the dispute that brought the United States and the Soviet Union to the brink of nuclear war. The delegates - who include politicians, military figures and academics from the US, Russia and Cuba - travelled to an abandoned silo west of Havana where Soviet nuclear missiles had been deployed. Amongst those present were the Soviet general who commanded the silo, Anatoly Kribkov, and the US spy plane pilot, William Ecker, whose aerial photographs were used to expose its existence. The crisis ended when the Moscow agreed to remove the missiles in return for the withdrawal of American nuclear missiles from Turkey.