It is sensible to let oneself be pushed around by Fate. I had already bought a guidebook to Sri Lanka when Catherine called; since our last meeting, in Tanzania, she and her husband had spent three years working in Laos. We lunched outside, in bright August sunshine, while Catherine’s boys – lucky lads, reared far from urban constraints – daringly climbed all over my roofs. And Catherine talked nostalgically of a mountainous country inhabited by gentle people, with a few tarred roads – a country as yet little touched, outside its two or three small cities, by consumerism and mass tourism. ‘But,’ she observed, ‘things are about to change.’ Already Thai television is watched along the western border – that is, on the left bank of the Mekong – many backpackers are arriving annually, motor traffic has increased since the opening of the so-called Friendship Bridge in April 1994 and developers are active. Soon the Laos she and Jan had known would be no more.

I heard then what I think of as my ‘inner click’, last heard before my Cameroonian trek in 1987. It happens when for some reason I am suddenly determined to visit a country previously unconsidered. Within an hour, Sri Lanka had been shelved.

Apart from Catherine’s information and Norman Lewis’s A Dragon Apparent – read soon after it was published, almost half a century ago – I then knew nothing of my next destination. A week later I was in London, buying a map and every available book on Laos; not many are available in English but quality makes up for quantity (see Bibliography). Settling down to a few months’ serious homework, I felt shamed by my ignorance. I had not realized the extent to which this misfortunate little country (in area the size of Britain, population 4.5 million) suffered as a victim of both Cold Warriors during the Second Indochina War – otherwise known, misleadingly, as the Vietnam War.

Laos, the map revealed, is walking rather than cycling territory. As it is a hot country, even during its cool season, I packed three sleeveless shirts and three pairs of knee-length shorts before turning my mind to more taxing matters, like visa complications (formidable) and the appropriate malaria cure (elusive). Then someone warned me that bare shoulders and legs offend Lao sensibilities, as do grubby travellers. It didn’t take long to replace the unsuitable garments but the Lao aversion to grubbiness might not be so easily dealt with at the end of a sweaty, dusty trekking day.

It seems odd that the wanderlust, unlike other lusts, does not diminish with age. As departure date approached my excitement level rose as uncontrollably as though I had never before left Ireland.