Simon Calder: To the ends of the Earth!

Seek, and you can find stimulating travel experiences almost anywhere. Indeed, while UK aviation closed down once again on a meteorologist's whim last Monday, I contented myself with a trip in search of attractions scattered around the M25. London's orbital motorway proved to be rewarding; I was cheered to discover that sushi is now available at South Mimms services. But over the decades the horizons of British travellers have dramatically expanded.

In 2010, the explorer's destinations are also to do with circuits, though less tangible and more exotic than the M25. While you may be content to work, study and raise a family within temperate latitudes, the explorer in you may yearn for the lush vegetation and ripe cultures of the tropics. The latitudes between Cancer and Capricorn are defined by startling diversity: the primary colours of Havana, the futility of the Sahara and the mountains of Borneo co-exist beneath the equatorial sun. But if you crave the raw edges of the world, then you should set your compass for the far north or south. Or, preferably, both.

The Arctic and Antarctic Circles are both defined as the lowest latitude where the midsummer sun never sets. Yet the polar regions they enclose could hardly be more different. The Arctic is an ocean surrounded by land, while Antarctica is a continent encircled by oceans.

How far is Antarctica? Well, even to reach the customary gateway of Ushuaia, you fly four hours beyond the most distant point ever served non-stop from Britain: Buenos Aires. By the time you make your way to the far south of Argentina, you will have problems telling east from west and day from night – which is just as well, because the tourist season coincides with the longest days. All the more light in which to marvel at the way the forces of nature converge on, and feed from, the Antarctic Peninsula and its many offshore islands: horizontal blizzards, penguins beyond number and icebergs the size of housing estates.

If you yearn to cross that magic Circle, however, you may be disappointed: this unforgiving part of the planet makes it difficult for all but the most determined (and expensive) expedition to cross the line.

From mild British latitudes, the far north is far more accessible than the deep south – and, washed by the Gulf Stream, far more benign.

Two hops and about six hours from Heathrow or Edinburgh can re-locate you in Longyearbyen, the fragile capital of Spitzbergen (and the northernmost town in the world). It lies so deep within the Arctic that you are closer to the North Pole than the Circle. But as with Antarctica, you are best advised to explore by ship. One day you glide through steely waters while an ornithological armada soars overhead, the next the vessel ploughs through sea ice with the consistency of lumpy porridge en route to a forlorn former settlement now patrolled by a polar bear.

Venturing to either end of the planet will recalibrate your experiences – and reawaken your sense of adventure. The edge of the world is nigh.