A variety of contributors write about the great dividing lines that cut off one people from another and mark the barriers between culture, language, religion and race. Some frontiers follow natural features such as rivers or mountain ranges, whilst others are the results of recent wars or old imperial bargains, but they are all man-made. Novelist and playwright Frederic Raphael explores the Pyrenees, the frontier between France and Spain. John Wells, the writer and actor, goes to the Iron Curtain to meet both East and West Germans. Award-winning South African author Nadine Gordimer visits the war-torn border area between Mozambique and South Africa. Richard Rodriguez, associate editor at Pacific News Service in San Francisco, investigates the meeting of First and Third World on the US/Mexican border. Ronald Eyre, who wrote and presented the BBC TV series "Seven Ages", meets those living on both sides of the border in Ireland, and finds cause for hope as well as despair. Nigel Hamilton, biographer of Montgomery, visits the hitherto relatively unknown boundary between Russia and Finland. The "Sunday Times" South-East Asia correspondent Jon Swain travels to the Thai/Combodian border where thousands of Cambodian refugees have been stranded for over ten years. Finally Christopher Hitchens, Washington columnist for "Nation" magazine and "Harpers", talks to Greek and Turkish Cypriots living on either side of Cyprus.