Great Journeys

From the Texas-Mexican border the Pan-American Highway snakes down through Central America and some of the world's poorest and most troubled countries. "To be perfectly honest, I was dreading this trip", declares the poet Hugo Williams as he sets off on a 3,000-mile drive through chronic political violence, weird religious practices and some of the hottest music in Central America. He finally comes to a standstill in the jungles of the Darien Gap, where the highway becomes a dirt track and Texas seems a long way away.

"To enter the Medina at Fez seemed to me to be whirled right out of the 20th century. Like Alice and the White Rabbit, we tumbled down and round into an extraordinary medieval world." Author William Shawcross sets off down the old Sahara Salt Road to find the camel caravans that still draw pillars of salt out of the fiery depths of the Tenere desert. His journey brings him in contact with a sultan, some dinosaur hunters and an ancient nation struggling to survive. By the remote salt pans of Bilma he finds Afarnou, a descendant of the fearsome Tuareg - once lords of the desert - and joins him as he hauls salt across one of the harshest trade routes in the world.

The Ho Chi Minh Trail is the most quoted legend of the Vietnam War. Now for the first time a westerner travels through the jungle landscape which concealed the troops, armaments and supplies as they headed south. Against massive American bombing and fire power, they had one dedicated aim — the liberation of Saigon and the unification of the country. Magnum photographer Philip Jones Griffiths, who recorded the war, makes an emotional journey awakening memories of a struggle that not only scarred the people but the conscience of the world. Picking his way through the still present debris of battle, he meets the Vietnamese who built the trail, journeyed and fought on it.

The South Sea Islands have always been portrayed as havens of exotic beauty - paradise on earth. During a wide-ranging search for the traditions of Polynesia, yachtswoman Naomi James soon discovers that paradise is under threat. Today the last remaining Pacific monarchy of Tonga, the hibiscus-strewn villages of Samoa, the carefree life of Tahiti and the clear and teeming waters of Bora Bora are enviromentally, politically and racially some of the most unsettled parts of the world. On this very personal journey Naomi re-examines her own preconceptions and prejudices as she comes to terms with what has happened since the arrival of 18th-century Europe on these exotic shores.

"As a child I always imagined that the earth had a heart and supposed that it must lie in the core of Asia." Colin Thubron, the celebrated writer, follows the traveller's old obsession - to find the centre of the earth. He takes the Silk Road from the ancient Chinese capital at Xian along the northern rim of the fearsome Taklamakan desert and into the remote mountains along the border between China and Russia. The Turkomen traders and farmers, whose ancestors made the Silk Road work, are still there, but they are not native Chinese. Holding fast to Islam, these forgotten people are virtually a nation on their own.

As the Soviet Union reels from one crisis to another, Norman Stone, Professor of Modern History at Oxford, wonders whether the ideology of Lenin can finally be buried once and for all? Making his first journey across Russia, from the frozen Baltic to the warmth of the Black Sea, Norman Stone is haunted by the greatness of the Tsarist past. "The Revolution was a terrible mistake," he says. Today, travelling through some of the most volatile parts of the country, he can see the scale of the Soviet mess confronting Mikhail Gorbachev's perestroika; food shortages, a collapsing economy, choking pollution and discontent. Is this the end of Communism? Now the Cold War is over, where does Russia go from here?

"When the Second World War ended, Burma turned its back on the world, drew up its bamboo drawbridge and put out a notice - do not disturb!" Travelling by steamer up the Irrawaddy River to Mandalay was the easiest part of Miles Kington's road to China - even then the boat went aground. Halted by a guerrilla war he flies on to pick up the road in remote south west China. Half a century ago this tortuous mountain route was the lifeline of Chiang Kai-Shek's nationalist army - today it's the artery of a thriving Burmese black market. The Burma Road is a secret route that both countries choose to forget.

With songwriter Billy Bragg and broadcaster/ Andy Kershaw. Even today the 17th-century silver routes of Bolivia are perilous. From the cyanide-weeping rocks of the Potosi mines, along a trail strewn with strange myths, customs and cultures, Andy and Billy trace a route to Chile and the seaport of Arica. Crossing this spectacular Andean landscape they meet the remote high-altitude Indians. As they witness the passion of ritual and the panoply of fiesta Billy responds in song, offering his own kind of music to a deeply moved but uncomprehending community.