As Mentioned on the front page of this section, train travel is indeed making a determined fightback against the pre-eminence of the jet plane. This may sound unlikely given the current plight of various bits of our own rail network, but in continental Europe at least, it happens to be true.

No doubt when George Stephenson launched his first locomotive back in the 1830s, people found the idea of it as fake and artificial as the aeroplane seems today. But all the same, cruising along at ground level does seem to have the edge on air travel in so many ways. Not only is it less alarming when a train stops in mid-track for no reason, but the view is a hell of a lot more interesting.

On a journey from London to Marseilles, for example, you can actually watch the sky clear and the landscape turn dry and rocky, as London slowly disappears, to be replaced by Kent, Picardy, the Isle de France, the Rhone Valley and Provence. Unlike flight - where you disappear into unseasonal sunshine within seconds of leaving Heathrow - train travel is basically just a speeded up version of walking.

With all this in mind, I have been speculating on the future of train travel not just in Europe, but around the whole world. On the suppostion that TGV trains will soon be built to travel at 350km per hour, the possibilities quickly become mind-boggling.

Consider cross-Asia travel, for example. Given that Peking is about 8000 km from here, a TGV version of the already existing Trans Siberian Express from London to the Great Wall of China would take just 24 hours. You could watch Europe merge into Russia, the Mongolian steppe and the Gobi Desert over the course of a day. For Hong Kong, add on another four or five hours; for Ho Chi Minh in southern Vietnam, another 10.

From chilly London to jungly Ho Chi Minh (via Peking) in under 36 hours? The sad side to such a fantasy is that this would actually be several hours faster than it currently takes to get from Hanoi to Ho Chi Minh on the "North South Re-unification Express".

If we move on to as yet non-existent stretches of rail track however, the fantasy becomes more outlandish still. Projects which have at least been mooted include a tunnel - which would not need to be as long as the Channel tunnel - under the Straits of Gibraltar linking Spain and Morocco.

Suddenly, direct trains to Marrakesh and Tunis would be on the cards. And given that Cape Town is roughly equidistant from the UK with Peking, a straight version of the rail line to South Africa that Cecil Rhodes once dreamt of could also be crossed by a hypothetical TGV train in 24 hours.

Even allowing for signalling problems somewhere along the way, that train would be so amazing that I think all African governments should unite in order to build it. But one other mooted rail project that would put even this one in the shade is a futuristic plan to link Asia with Japan and the Americas by a series of tunnels.

One of these tunnels would link South Korea with the Japanese island of Honshu. Another would wend its way north from Hokkaido along the Kurile Islands, a string of dots leading up to the Kamchatka Peninsula in eastern Siberia (the fact that ownership of these Kurile Islands is a subject of dispute between Russia and Japan will not matter much in the 22nd century).

From eastern Siberia it would then be a relatively simple matter to complete the final stage of this grand project, namely to build another tunnel under the Baring Straits to Alaska.

Having made the link with the North American rail network, trains from London would soon be steaming into Los Angeles and New York City, not to mention Bogota, Rio and Tierra del Fuego. London to Tierra del Fuego? Even at 350 km per hour, that would be a longish trip, of perhaps three or four days, though presumably the train will have comfy couchettes and plenty of hot water. I hesitate to guess on the price of a return ticket but I think we had better start saving soon.