Fancy that! Granny in a spaceship © Jay Kinney & Paul Mavrides

The problems involved in traveling in the empty spaces that now exist will be nothing compared with the interminable negotiation that will occur in the future. Wild animals are rarely a problem anywhere; the only real danger anyone is likely to face is another human being.

Amazingly, just a dozen years ago some people in the Highlands of New Guinea could still recall the day in 1930 when they saw their first outsiders-Australian gold-seekers-whom they took to be their zombified ancestors, traipsing back from the dead.

Even today, some hinterlands in the world still exist. God bless the thoughtful islands/ Where never warrants come, Kipling wrote. But of course it is only a matter of time before they are violated. I have witnessed such a transformation in a number of countries. When I first traveled to Puerto Rico in 1961, Sicily in 1963, Uganda in 1966, Afghanistan in 1973, Honduras in 1979, the Upper Yangtze River in 1980, and Albania in 1993, I felt in each place that I was in a time warp. But after me came a deluge-soldiers, nationalists, tourists, developers, or civil war-and those places have been profoundly changed, if not corrupted in new and perverse ways.

Travel changes from year to year, because countries open and close, the world contracts and expands, countries and governments and frontiers alter. Yet the going is still good, and even at its most awful, travel can be illuminating, especially to an ironic wanderer who despises nuisance but takes a grim satisfaction in hardship.

In spite of our new connectedness, we have very little idea what is really happening in Algeria - or in North Korea, rural Tibet, or the eastern Congo. The Solomon Islands in the Western Pacific are not visited by many travelers, even today. For that matter, there are many uninhabited islands off the coast of Maine. The wooded, not-very-populous Malawi I first saw in 1964 as a Peace Corps volunteer is nothing like the deforested and overpopulated Malawi of today. A century hence, it will certainly be another place, awaiting rediscovery.

It is a pompous conceit to pretend that because a place has changed - or has lost its exoticism - it is not worth seeing; that very change qualifies it as a destination.

Of course, wealthy people will always pay to be dragged up Everest, or parachuted onto the Equator, or hurried in and out of Antarctica before frostbite can take hold, or to cruise luxuriously up the Amazon.

I once met the astronaut Buzz Aldrin and gushed over his achievement. He replied, "Your grandmother could do what I did." Fancy that! Granny in a spaceship, Granny being weightless, Granny saying, "Oh, dear!" when a solar panel breaks loose.

Much of futurology is idle speculation. We cannot know what the world will look like 100 years from now - travel is a human imperative. Enlightenment will always involve the poetry of departures.