Royal Caribbean Oasis of the Seas: a playground on water

The world's biggest cruise ship is full of fun for the more discerning cruiser

To say this ship is large is a bit of an understatement. At 360 meters, it's as long as three and a half football pitches, making it officially the world's largest cruise ship. Stood on its end, it's taller than the Eiffel Tower, although I'm hoping we won't get to see it from that angle. It's wider than New York's Park Avenue and Madison Avenue combined. And at 225,282 tonnes, it's as heavy as 1,204 blue whales. These titanic proportions mean it can fit over 6,000 passengers, plus a couple more thousand crew. So, it's quite big.

As such, there's plenty to get up to while at sea. It's the world's first cruise ship with a zip line, so should the urge take you, you can slide down it while people on the boardwalk below look up in awe. If you want to catch some waves without breaking your "nothing goes overboard" policy, there are two surf simulators, called Flo Riders, to try out. You basically stand on a fake surfboard trying to withstand everything a wave machine can throw at you. Next to them is a basketball court, and across to the other side of the deck are four pools, ten whirlpools, an aqua park, and a miniature golf course. And that's just one of the 17 decks.

Down below you've got two rock climbing walls, a fairground, an aqua theatre (think Sea World meets Cirque De Soleil), an indoor theatre showing Hairspray, 24 restaurants ranging from steak houses to world cuisine, and more bars than even the most dedicated reporter can get round in one day. There's a covered walkway called the Royal Promenade, with shops, more places to eat and an English pub you can smoke in, complete with faux paving. It's like a cross between a Vegas hotel and a UK shopping centre. Except of course, this ship has more guest rooms than your average Vegas hotel.

It has its own open air park, called Central Park, with 12,000 plants and trees that are maintained by a series of pipes claimed to be 90 per cent more efficient than a regular sprinkler system. About all that's missing is an expanse of undulating hills.

The list of onboard options goes on: there's a jazz bar, a comedy venue, a slightly tacky night club, a spa, a library, a gym and a running track that goes around the circumference of the ship, an ice rink... and pretty much everything else you could need. And that's before we get onto the technology involved.

Upon boarding you're issued a swipe card called a SeaPass card. This opens your room door, but also accesses an onboard expense account, so you swipe it in the shops to buy stuff, with no need to carry cash or credit cards. It's also a security measure: during a drill or emergency, ushers swipe the cards on PDAs to keep track of where everyone is, ensuring they're accounted for. It's a system they call electronic mustering, and is far more advanced and reliable than pen and paper. Oasis of the Seas is the first to use it.

While the Safety Command Center is in the bridge, it's kept separate from the navigational controls, with dedicated members of staff, leaving the captain free to look out for icebergs. No fewer than 1,300 CCTV cameras minimise the chance of mishaps. And with a floorplan beamed onto the wall using a projector, staff can lock fire doors independently of each other using magnets to isolate areas. It's clever stuff.

If you're feeling paranoid you can keep a look out for potential hazards yourself using Shipcam, a video camera that gives a live feed on your TV of what's going on outside, as well as a map of your location. And should the alarm be raised, there are 18 lifeboats, although as each one fits 370 people and they are powered by engines, they're more like separate ships than rubber dinghies.

Disappointingly, there's no big wheel to steer the ship just a tiny joystick. Captain William S. Wright keeps the behemoth computer controlled most of the time, like autopilot on a plane, with 135,000 horse power chugging it along at an average of 22 knots. During 90 minutes of loading in one port, it moved just 40cm while on automatic. "It's a dream to handle," he told us, "as responsive as a Ferrari." Just with a slightly larger turning circle.

By each bank of lifts there are huge touchscreens showing where you are and suggesting what to do. And there are more screens dotted around telling you how full each of the restaurants are with a thermometer-style measurement, so you can plan your dining for atmosphere or peace and quiet.

This is cruising on a previously unimagined scale, but still maintains the authentic cruising atmosphere. Seeing a short bald man sing I Believe I Can Fly in a karaoke bar on board one night confirmed that much.