St Maarten, an island that forms part of the Netherlands Antilles, is already having to redesign its port facilities after opening a new cruise terminal in 2000. "Mega-ships for mega-ports for mega-bucks. That's what it costs," said Commissioner Heyliger.

He says that four mega-ships simultaneously offloading 10,000 tourists, something that he sees as happening shortly, would overload port and infrastructure facilities throughout the island. However, the boom in tourism is being matched by economic growth. Heyliger recently said that economic activity in 2006 may have been up on 2004 by as much as 30%.

The largest cruise liner yet built, the 160,000-tonne Freedom of the Seas, set sail from Southampton last year; the Finnish-built ship has 15 decks with more than 1,800 state-rooms for up to 4,375 passengers, and is 339 m (1,112 ft) long. Freedom's facilities include a family water park, a full-size boxing ring and an onboard surfing pool with its own wave machine which simulates surfing a 10-foot-high ocean wave moving at 20 mph.

Freedom won't be the world's biggest liner for long, though. Royal Caribbean is planning a 220,000-tonne behemoth for 2009, code-named Genesis, which will carry up to 5,400 people and be 1,180 feet long.

The yachting sector is also seeing a trend towards more and bigger vessels, which puts strain on marinas designed for smaller craft. The US subsidiary of Dutch luxury yacht builder Feadship, for example, says it received 435 orders for ships of over 30 meters (100 feet) in length last year, up from 87 in 1998.