Cruises are undergoing something of a renaissance. Growing numbers of younger cruisers means on-board activities and shore excursions are becoming more active, flexible and fun. Jane Archer explores the burgeoning world of the 21st-century cruiser.

Who says cruising is for old people? Big cruise ships these days are packed with activities that are great whether you are five or 55. Children can have hours of fun in the kids' clubs and dipping in and out of the swimming pools, and there are huge and luxurious spas and solariums where adults can relax and be pampered.

But there is so much more for the 21st-century cruiser: rock-climbing walls, ice-skating rinks and water parks, celebrity-run speciality restaurants in which you can dine like the stars and adrenaline-packed shore excursions for fun days in port.

On-board activities

Not so long ago, napkin-folding classes were considered the perfect way to keep passengers occupied when they had had enough of looking out to sea. There are still sessions on how to be the perfect hostess, and many ships have cookery demonstrations and wine-tasting sessions, but such gentile occupations are fast giving way to much more active ways to pass the days at sea.

Royal Caribbean International's Voyager-class ships (for instance - Voyager of the Seas, Liberty of the Seas, Independence of the Seas) have rock-climbing walls and ice-skating rinks, but also a FlowRider, a powerful wave you can surf on, and water parks with fountains, jets and even a lazy river.

It's all terrific fun, but things get even better at the end of 2009, when Royal Caribbean launches Oasis of the Seas. This is a huge ship, holding 5,400 passengers. As well as all the features above (and actually there are two walls and two FlowRiders), there is a zip wire - get harnessed up and slide on a wire across the top of the ship - and the first carousel at sea.

Norwegian Cruise Line has 10-pin bowling alleys and Wii Sports games on its newest ships - Norwegian Gem and Norwegian Jade. Its next new ship, Norwegian Epic, launching in July 2010, will have the first ice bar at sea. Passengers will be kitted out in fur coats, gloves and hats, and be able to drink ice-cold vodkas in freezing temperatures.

Water slides are a favourite with Carnival Cruise Lines and Italian line Costa Cruises. On new ship Carnival Dream, launching in September 2009, there will be a four-deck-high water slide and a two-lane racing slide.

Ocean Village has juggling and trapeze workshops to keep kids of all ages entertained on days at sea; P&O Cruises has bungee trampolines on deck 19 of Ventura, offering the ultimate view across the sea if you dare look up; guests on Cunard's Queen Victoria can learn sword fighting.

If all that sounds too energetic, Princess Cruises has the ultimate behind-the-scenes tour on Ruby Princess, letting guests visit the engine control room, laundry, food stores, bridge and theatre, and even climb into the funnel. On sea days, Holland America Line holds galley tours lasting about 30 minutes: passengers can pass through the kitchens, watching the chefs in action and tasting on the way.

A taste of celebrity

Traditionally, evening dining on a cruise ship meant eating at the same time every night, sharing with other passengers on a pre-allocated table. Passengers can still do that, but cruise lines these days are increasingly flexible, offering alternative ‘eat-when-you-like' options in the main restaurant.

More than that, most cruise lines have speciality restaurants that cost extra - the food served in the dining room is included in the cruise price. Princess Cruises has the Crown Grill, serving steaks and other cuts of meat, and also Sabatini's, where guests munch their way through 12 or so courses, with antipasti, pizzas, pastas, salads and soups all on the menu. Norwegian Cruise Line ships have up to 10 restaurants, with French bistros, Mexican diners and sushi bars included in the mix.

Recently several cruise lines have gone another step further and signed up celebrity chefs to run their speciality restaurants.

Gary Rhodes has restaurants on P&O Cruises' Arcadia (Arcadian Rhodes) and Oriana (Oriana Rhodes), serving up food best described as "Brit with a twist", while Marco Pierre White ("contemporary with an Italian essence") has designed the menus served in the White Room on P&O's newest ship, Ventura.

Ocean Village has The Bistro, on the ships Ocean Village and Ocean Village Two, serving menus designed by James Martin (expect "British with a hint of the Med"). Martin was voted the favourite celebrity chef at sea in a Cruise Critic poll in March 2009.

Sushi king Nobuyuki ‘Nobu' Matsuhisa (serving "Japanese with a European twist) has a restaurant and sushi bar on Crystal Cruises' two ships, Crystal Serenity and Crystal Symphony.

Aldo Zilli ("classic Italian") has teamed up with Thomson Cruises and has a speciality Italian restaurant on Thomson Celebration.

Several cruise lines have celebrity cruises, when top-name chefs come on board to host cookery demonstrations and cook up sumptuous meals.

Celebrity chef Raymond Blanc, Martin Burge, head chef at Whatley Manor in the Cotswolds, and Colin Bussey, former executive head chef at Gleneagles Hotel, have cruised with Silversea Cruises; in October 2009 Anton Mosimann will be on board Silversea's Silver Wind. Jacques Pépin, chef to three French presidents and executive chef with Oceania Cruises, often cruises with Oceania. His next cruise is in August.

Active shore excursions

Cruise lines still sell sedate coach excursions, allowing older passengers to see the sights without too much effort, but as cruisers get younger, so the ships' tours are a lot more exciting.

Ocean Village has some of the best days out - canyoning in the South of France (this involves donning a wetsuit and clambering over boulders as you make your way down a fast-flowing river), and swinging, sliding and zipwiring between trees in Corsica. Ocean Village ships also carry a fleet of bikes and there are city tours by pedal power for anyone feeling fit.

Zip-wiring through trees in a harness has become a hugely popular excursion. Princess Cruises offers it in Alaska and Jamaica, where it is combined with a thrilling bobsled ride. Princess also has river-tubing in Grenada.

Carnival Cruise Lines has a survival adventure in Belize. Passengers will learn to make fire without matches and cook jungle-style. Celebrity Cruises has helicopter flightseeing trips over Hawaii, with the chance to see an active volcano.

Passengers with a few thousand pounds to spare visiting Livorno on a P&O Cruises' ship can hire a Ferrari F430 for a day; a cheaper option is a bike ride in Alicante. It's mostly downhill, great fun and there's a slap-up local lunch after to celebrate.

Windstar Cruises has a new selection of tours in Europe, including helicopter rides over Monte Carlo and Mount Etna, speedboat rides in Croatia and Portofino and underground cave trekking in Koper, Slovenia.

You can take thrilling speedboat rides around the Stockholm and Helsinki archipelagos; go into the network of tunnels outside Ho Chi Minh City where the Viet Cong lived during the Vietnam war; even pilot a Russian MiG fighter over the skies above Moscow. All these are offered by Crystal Cruises, to those who want the ultimate thrill.

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