Wind cracks through the sails on the replica 19th-century schooner. The tourists stir and readjust their limp bodies on deck, irritated by the canvas' shadows. They are stripped and slathered in sun lotion, greedy for the bronze rays, even while cruising the legendary bay of Thira.

The five islands are better known as Santorini, the star of the Cyclades - and countless Greek promotional posters, which peddle the whitewashed walls, azure domes and sheer volcanic crescent of cliffs, cutaway like a child's diorama, revealing the Aegean's geological secrets.

The saltwater swirling through the crater - the caldera - sparkles sapphire, emerald, turquoise; the startling hues of a gem shop, a peacock's tail. Its clarity inspires vertigo, revealing depths up to 600m. On the ocean floor, lie Minoan ruins, submerged 3,650 years ago by a mighty eruption. Romantics, including Plato, claim the sophisticated civilization destroyed was Atlantis.

The blast - the most powerful in human history - detonated with the strength of 150 hydrogen bombs. Ash scattered over the globe: Frightening royal scribes in Egypt with nine days of darkness, drifting over China, inhibiting the growth of pines in California. Three-quarters of Santorini vanished, leaving only a rind, curving around a six-kilometer wide bowl of blue.

Such scenery defies description, bankrupts the English language. The raw beauty even stymied the prolific pen of Lawrence Durrell. "Prose and poetry, however winged, will forever be forced to limp behind," he admitted in The Greek Islands. "Perhaps only in the fanciful reaches of science fiction will you find anything quite like this extinct volcano of white marble, which blew its head off at some moment in the Bronze Age."

The daytrippers aren't scrabbling for vocabulary, however. They're more concerned with the supply of coffee, cigarettes and cokes, those items indispensable to holidays in European hotspots. Everyone ignores the record rattling over the loudspeaker, clunky descriptions of the sights in Greek, English, French, Italian and German. (CONTINUE...)