Historian and writer Dan Cruickshank celebrates the creative force of architecture as he explores the world's greatest cities, buildings and monuments. Dan explores buildings shaped and threatened by disaster. He risks his life to visit the Minaret of Jam in Afghanistan, a monument to peace and tolerance in the midst of a war zone. San Francisco is preparing for a cataclysmic earthquake - what role can architecture play in saving lives? And Dan reveals the tragic tale of Palmyra in Syria.