All your desert-island fantasies come true as you approach Zanzibar. Indeed, all the fantasies you ever had about travel suddenly crowd around. The sea is preposterously aquamarine, the sand implausibly golden and the airport impossibly empty. Check the map in the in-flight magazine to make sure that you are not dreaming, and that there is indeed an island the size of the Isle of Man bolted on to the right-hand-side of East Africa - close enough to benefit from the richness of the continent and its people, far enough to have been regarded as a safe staging post by early colonists.
An empire was hardly worthy of the name if Zanzibar was not included as a conquest on the Imperial bedpost. Persians and Portuguese, Indians and Arabs all took turns at controlling the 20-by-50-mile patch of land poking out of the Indian Ocean. It was the Arabs who endowed the place with its sense of dreamy intoxication by starting the spice industry and bestowing the inevitable cliche of the Spice Island, assiduously milked by the tourist board.
Still, if your home smells as headily sweet as this, then you can forgive the marketing people anything. I visited Mr Madawa, a spice merchant who gives hands-on explanations of the wondrous fumes that waft randomly around the islands. As he slices a sliver of bark, the scent splashes deliciously into the heavy noon air. Then he takes you and a handful of aromas back to his modest home to take apart any preconceptions you may have about the unsophistication of African food. Lunch is labour-intensive, but then Mr Madawa has four wives. His team of spouses (or should that be "spice"?) conjure magical dishes from an island where few tricks are needed to grow effusive quantities of exotic tropical crops.
Mr Madawa has a plurality of wives because the brand of Islam that prevails on Zanzibar permits polygamy. Much of the social structure - as well as architecture - was imported from the most easterly Gulf state, Oman, in the last century. At one point, the Omani court moved 2,000 miles south to take advantage of the benign terrain and benevolent society.
British hegemony soon prevailed, adding another layer to the cultural veneer that makes Zanzibar so confusing. To confound yourself utterly, rent a bicycle from the thoroughly African market. It will probably be a Raleigh, based on an original idea from Nottingham. The plans, though, were long ago taken to India, where the upstanding Roadster flourished. This sturdy machine will take you through a maze of lanes as intricate as any Arab souk, until you reach the bleak block of flats where Freddie Mercury grew up.
The late, great Queen singer was born to a Shirazi family, of Iranian descent. Freddie Mercury was blessed with an upbringing on an island of plenty, where your neighbour was as likely to hail from Delhi as Dar Es Salaam. People go gently about their modest business in a climate where moderation is the key. Stress is merely something you put on the first syllable of Stone Town, the closest thing to a capital that Zanzibar possesses. As a shambles it is superlative, layer upon layer of humanity leaving its languid mark on the paraphernalia of government. The House of Wonders was the venue for the shortest war in history 100 years ago, when the British put down a little local difficulty in a little over half an hour. Now the House is a doddery old pile of quasi-Imperial clutter that looks as if it was under siege for 38 years, not minutes.
Most of Zanzibar is untroubled by urban life, and comprises a lolloping landscape where Mr Madawa's spices vie for light with arrogant palms. If you scrunched up the page of the atlas which deals with land use - all dark greens and deep reds, vivid blues and sandy yellows - then smoothed it out, the rumpled result would resemble rural Zanzibar. That spectrum coalesces at a single point at the tip of the island: the beach at Nungwi, where a placid village peeps out from the palms at a mile of virgin sand. The alphabet ends here - as does the traveller's quest for perfection.
You can reach Zanzibar via Muscat on Gulf Air, for around pounds 600 through discount agents; or arrive by boat from Dar Es Salaam, having flown there on a cut-price ticket on an airline such as Ethiopian Airways for about pounds 450 return; or take a cheap charter to Mombasa, connecting there with the Kenya Airways shuttle to Zanzibar. You will need a Tanzanian visa, obtainable relatively painlessly from the Tanzanian High Commission (0171- 499 8951). The most sensible guide book is the Bradt Guide to Zanzibar by David Else, price pounds 7.99.