It's an ugly rock in the Atlantic, battered with sand from the Sahara. But one in 10 of British package tourists go to Tenerife, and Simon Calder can see why
Don't go to the Sahara. Just visit Tenerife and wait for the desert to come to you. The largest of the Canary Islands is the pork chop-shaped isle of Tenerife, and its nearest mainland neighbour is the Western Sahara. If the wind is in the right (or wrong) direction, everything gets doused in a fine layer of sand.

If a sandy slab of volcanic rock measuring 30 by 50 miles does not sound desperately promising as a holiday destination, you should know that one in 10 of us who take a package holiday every year choose Tenerife. Leaving aside the odd bout of sandblasting, the weather is reliably warm and sunny, and the tax-free status of the Canaries makes Tenerife even better value than mainland Spain.

Which helps to explain why Las Americas has sprung up. The beach resort that straggles clumsily along the south coast has a strangely symbiotic relationship with the landscape. Volcanic rock looks remarkably similar to builders' rubble. So the half-hearted and half-finished apartment blocks blend in well with the environment.

Yard upon scruffy yard of the seafront is crammed with bars which themselves are packed with drinkers, rigidly differentiated by nationality and beer. The Dutch sip Heineken, Germans swig Holsten, Brits swill Guinness and watch Fawlty Towers videos.

The Sahara has not been sufficiently generous with its overnight sprinkling to disguise the fact that the beach is unappealing grey, because the sand is volcanic. The warm Atlantic, though, compensates. I like the resort's raucous honesty; some might accuse it of wreaking cultural GBH on the island's soul, but no sensible Spanish person would be here at all were it not for the tourists. And anyway, normal life is just a bus ride away.

Infused with humanity and humour, decorated with panache, draped with drama; this description would not apply to Las Americas, but it fits the capital, Santa Cruz, perfectly. The city market is named Our Lady of Africa, and feels commensurately Moorish. Whispers of gossip and wisps of smoke curl out from the huddles of workers drinking rough red wine and biting into harsh chorizo and piquant cheeses. Their faces, crumpled by sun and breeze (and probably the odd sandstorm), dance animatedly as they chew, and indicate a life spent in a different world to the beach resorts.

The few tourists who make it as far as Santa Cruz identify themselves by noisily slurping Fanta, and carrying the air of having stumbled upon the Real Spain. But economically, the Real Tenerife is back there on the beach. The island has little cultivable land, and what there is tends to be obliterated by plastic sheeting - an ugly but effective strategy for enhancing agricultural output. So most locals regard tourism as benign, and are correspondingly benevolent towards visitors. If there is a rogue taxi driver or a grumpy waitress, then neither I nor anyone I talked to had encountered them.

As the clouds begin to clear, the spectacular truth about Tenerife becomes apparent. The island has a third dimension, a volcanic peak piercing two miles into the sky. The 12,000ft summit of Pico del Teide is Spain's highest point. The mountain is only 20 miles north of Playa de las Americas, but the tortuous road journey takes a couple of hours. On the way you pass through a succession of decreasingly affluent villages, until you hit Vilaflor. This gently crumbling jumble of cottages is Spain's highest settlement. The sea is a vertical mile below, and long since obscured by low cloud.

Hereabouts you leave planet earth and set foot on the moon. Until lunar tourism becomes a possibility, the best way to emulate the ghostly, rugged vacancy of the moon's surface is to take the road through the volcano's caldera. The peak itself is surrounded by the debris of the eruption, 15 million years ago, that thrust the Canary Islands through the surface of the Atlantic. The frozen, writhing rock creates a thoroughly alien environment, one protected by being a National Park. Yet in the middle of it, someone has plonked a cable-car station.

Among old Tenerife hands, the tales of the queues for the teleferico ride to the top are a favourite topic of conversation. Four hours seems to be the longest wait of those who stirred themselves from the beach. But when I went there was no one.

The view on a clear day, they say, is magnificent, across to the neighbouring islands and even to Africa. But I did not see much of anything beyond the immediate surroundings: a deathly and contorted landscape. At this altitude snow has replaced sand as the icing on the rock cake.

The heat of sea level becomes a delicious prospect, and you return to the crowds on the beach with relief. One in 10 of us has the right idea - this is, indeed, the life. And if you tire of the warm and gentle indolence which is the main attraction of Tenerife, you can always escape. Just hop over to the neighbouring island, which was Christopher Columbus's springboard to the New World. If he could explore, so can you.