Q. My brother has lived in Cambodia for many years and now wants to return to Ireland. The problem is that he cannot fly because of medical problems - related to blood circulation/thrombosis. Can you suggest a possible alternative?

Peter Kelly

A. The overland journey from Cambodia to Ireland is straightforward, if occasionally tedious and quite expensive. Your brother should begin with a bus from Phnom Penh, the Cambodian capital, to Ho Chi Minh City (formerly Saigon) in Vietnam. (This is, if you care to look at the map, aiming directly away from Ireland - but necessary given the way that geo-politics and the railways work.)

The Reunification Express to Vietnam's capital, Hanoi, takes 29 hours, with some great scenery along the coast and through the Hai Van Pass. An international train from Hanoi to the Chinese capital, Beijing, runs twice a week and takes 36 hours. The Trans-Mongolian link between Beijing and Moscow is one of the world's very greatest train rides. It runs twice a week and takes six days. Moscow-London takes 48 hours via Berlin and Brussels, where you pick up the Eurostar to London. The final stretch involves a short walk from St Pancras to Euston, followed by a train to Holyhead in Wales and a ferry across the Irish Sea. In theory, if connections were kind, he could cover the ground in two weeks. But it would be calmer to reckon on about 20 days' travel, allowing for a day or two of recuperation and sightseeing in Hanoi, Beijing and Moscow, for a total cost of perhaps £3,000 - and a lot of work sorting out visas for Vietnam, China, Mongolia, Russia and Belarus.

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