Our honeymoon, my fiancée suggested, should involve swimming with beautiful fish. Swimming with a dolphin would be good, too, she added, possibly unaware that the experience came out top in last year's BBC poll of 50 things to do before you die and that dolphins might now draw a crowd.
A process of elimination led us to Belize, home to the northern hemisphere's longest barrier reef. Stretching for over 100 miles, the reef and the surrounding Caribbean waters are home to some of the world's most beautiful fish. Snorkelling with sergeant fish, squirrel fish, parrot fish and stingrays satisfied the highest expectations.
It was while trying one of the country's other great pleasures - staying on one of the numerous, small and beautiful cayes (islands) - that we got wind of our big fish. A fellow tourist had taken a trip to dive with whale sharks, annual visitors to the reef.
Imaginations fired, we headed for Placencia, a beach town and whale-shark-watch central at the southern end of the country. There, near a break in the reef called Gladden Spit, the whale sharks gather between April and June each year. This period is the spawning season for local fish species such as the snapper and the jack, and the sharks travel miles to feed on the millions of eggs released every day by these fish. Despite sharing a genus with some of the most toothy predators of the sea, these fish are filter feeders, surviving by sieving the sea for plankton like the whales after which they are named.
We joined a trip run by the Seahorse Dive Shop. Though neither of us knows the first thing about diving, we had grasped the basics of snorkelling. Brian, the dive master, and one of the country's most proficient whale-shark guides, assured us that when these creatures appear, they often ascend to quite close to the surface, making them visible to both divers and snorkellers.
The first dive was a qualified success. To attract the sharks, the divers mimic the spawning: they descend to around 100ft, gather in a tight group, then exhale in unison. The resulting stream of bubbles appears to the hungry whale shark like lunch and, as a result, they are drawn to investigate.
We snorkellers circled on the surface, keeping pace with the stream of bubbles as it broke the surface. With no whale sharks visiting, we followed a school of snapper hoping that the whale sharks would prefer the real thing to the froth provided by the divers. No shark appeared but a family of dolphins did - three adults and a teenager. They swam around us for a few minutes, then slipped away. A hawksbill turtle also showed its face.
We had lunch at nearby Silk Cayes; grilled local fish and salad. The cayes are home to a team of biologists, led by workers from the University of York, that studies whale sharks and monitors the marine reserve of which this area forms a part. Afterwards, we returned to the gap in the reef, where the divers descended again to huddle and blow.
At first, we only glimpsed the whale sharks passing in the distance, just a shadow of brown at the limit of visibility. Then, in a matter of seconds, we were among them. Though seeming only to gently wave their great tails they passed by quickly, and each seemed as big as a railway carriage. At one point, we were among a group of seven and I watched one swim by about 20ft away, its tag clearly visible behind its dorsal fin. Others loomed into view disconcertingly fast from the depths. The diver's ploy had worked. But as the afternoon light lengthened, so the spawning started for real and this was our cue to leave the water to the sharks and their meal.
As the divers surfaced, the waters around where we had swum began to bubble and boil with the released spawn of the snappers. As the last diver hauled himself over the side, the sharks began to feed, swimming through the turbulent water, mouths open, their heads and backs clear of the surface. We stayed to watch them for a while. Then as the light began to fade, we turned for home.
Some of our fellow passengers had booked this trip two years before and were ecstatic that the wait had been worthwhile. Others, like ourselves, had turned up the day before. However, no one would forget it in a hurry.
Getting there: Trailfinders (020-7938 3939, trailfinders.co.uk) offers flights to Belize City from £539 (plus tax) via a US city. Tropic Air (+226 2012, tropicair.com), flies Belize City-Placencia for $140 return. The bus is much cheaper and takes three hours (timetable and fares: belizecentral.net/bus_schedule/schedule.html).
Where to stay: Ranguana Lodge, Placencia (+523 3112, ranguanabelize.com), has beachfront cabins with shower for $64 inc tax.
Activities: Brian Young from the Seahorse Dive Shop (+623166, belizescuba.com) can arrange all types of snorkelling and diving trips from $50 including equipment and lunch. April and May are the best months to see whale sharks.
Furthur information: Belize Tourism Board, New Central Bank Building, Level 2, Gabourel Lane, PO Box 325, Belize City (+223 1913, travelbelize.org). Country code: 00 501. Flight time: London-New York 7hrs 45mins; NewYork-Belize City 5hrs; Belize City-Placencia 45mins. Time difference: -6hrs. £1 = 3.57 Belize dollars.
