By Heida Sarna and Terry Ward

updated 3:08 p.m. ET July 7, 2008

For cruise critic Anne Campbell, one particular moment during a snorkeling excursion on a Mexican cruise stands out as testimony to mass cruise tourism’s toll on the authentic travel experience.

“We had taken a smaller boat about 45 minutes away from the port at Cabo San Lucas to a snorkeling spot, a beach, and when we arrived, there were no fish to be seen,” recalls Campbell, Editor of Cruising from New York, an online guide detailing cruise departures from New York City’s three terminals, “So our guide pulled out a canister of Cheese Whiz and squirted it into the water, and it was like a million fish came around.”

But when it comes to cruises, your first hint that the experience is not going to live up to your exotic expectations will likely come as you steam into port.

“In Baja and the Pacific coast of Mexico, you’ve got a problem because there are a lot of ships doing week-long cruises from San Diego and Los Angeles, year round, and these ports are just swamped,” said Campbell, “You pull into places like Mazatlan, Cabo San Lucas and Ixtapa, and they are simply overrun with ships.”

Indeed, any dreams cruise passengers have of secluded beaches for sunset strolls, isolated stretches of coastline for kayaking — even just a private corner of deck where you can canoodle with a romantic view — are more than likely just that: Dreams.

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Cruise line ads work hard at trying to convey exclusivity, intimacy and seclusion. But in reality, the more than ten million people who cruise every year go to a lot of the same places. Tour buses line up at the docks like advancing armies, while sign-waving guides and freelance touts vie for passengers’ attention. And it’s not only Mexico and the Caribbean where overcrowded ports seriously threaten a serious deluge on your cruise parade.

Take Alaska. Overall, the number of cruise passengers to Alaska has more than tripled since the early '90s, according to the North West CruiseShip Association. Juneau is the state’s busiest port, with some 650 cruises calling in during the summer months. Juneau’s local population hovers around 30,000 and on an average day during high season, more than 5,000 cruise passengers fan out around the small town, piling on buses for trips to Mendenhall glacier and other local attractions.

“You can practically walk from Vancouver to Seward across the tops of cruise ships during the summer months because there are so many boats,” said Campbell.

Lynne Sladky / ASSOCIATED PRESS During the prime winter months in Phillipsburg, St. Maarten, traffic jams, packed shopping strips and wall-to-wall beach towels at Great Bay Beach in town are par for the course.

In St. Thomas, an island just 13 miles long and four miles wide, almost two million tourists arrived by cruise ship in 2006, according to research consultant G.P. Wild International Ltd. Six to eight giant ships a day is business as usual at this Caribbean evergreen — we’re talking more than 20,000 cruisers on an average day heading for the same few beaches and attractions.

It’s the same deal in Nassau and St. Maarten, where traffic jams are as prevalent as sunburns and hangovers.

Usually the smallest ships, carrying just 100 or 200 passengers, don’t make a dent.

In the cruise world, “exclusive is a synonym for ‘small ship,’” said Campbell, and the smaller and more upmarket your vessel, the more likely you’ll be to avoid the biggest and busiest ports.

It’s the 2,000-plus passenger boats that are most likely to pull into the sardine-packed ports. Behemoths like Royal Caribbean’s new Liberty of the Seas can carry more than 4,000 passengers, and half that in crew. The weekly rotation includes Cozumel and Grand Cayman or St. Maarten and San Juan.

The Caribbean has been the number one cruise ship destination for years. In both 2005 and 2006, the Caribbean accounted for about 40 percent of the North American-based cruise fleet, according to the Cruise Lines International Association (CLIA), a trade group. The Mediterranean and Europe roped in about half as much cruise traffic during the same time period, followed by a virtual three-way tie by Alaska, the Bahamas and the Mexican Riviera, each just under about 10 percent of the total market. But it’s not just the numbers of tourists descending on a port that make or break the experience — port size matters.

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