Every fall, cruise lines move many of their ships to new seas and climates on what they call "repositioning" cruises. They discount the rooms--charging less than $120 a night per person for interior rooms, for example--because these itineraries are generally one-way and hit passengers with the additional cost of buying one-way plane tickets home. These cruises also usually last longer than seven days, which isn't to everyone's taste, so cruise lines try to make these trips more attractive with lower prices. As a rule, passengers pay less per day for these longer cruises than for standard ones.

The most interesting repositioning cruises are in the fall, says Paul Motter, editor of Cruisemates.com. The reason: Fall is when some cruise ships return from a summer in Europe to head down the East Coast, while other ships return from a summer in Alaska to head down the West Coast.

Here's a sampler of deals, with rates starting at $479 for six-night cruises on ships with standard amenities and rising to $1,700 for 13-night cruises on luxury liners. Rates are based on double occupancy and include taxes and port charges....

New York City to San Juan, Oct. 20-27, 2007. On this route, Princess Cruises sends its Crown Princess to its winter circuit in the Caribbean, stopping along the way at St. Thomas and Antigua. The six-night Atlantic coast cruise is a bargain, with starting prices at $479 per person for interior cabins. When we recently looked at one-way flights from San Juan to New York City, the lowest fare we saw was $141 a person, flying on American. 800/774-6237, Princess.

Southampton, England, to Fort Lauderdale, Oct. 30 -- Nov. 11, 2007 On its way from Southampton to a route off the shores of Scandinavia, Royal Caribbean's Jewel of the Seas stops in Le Havre (near Paris), La Coruna, Funchal (near Madeira, Portugal), and Brussels. This 12-night tour costs $899 per person for a family-sized, ocean-view cabin. That's $75 a night, versus $122 a day for the same room on a nine-day route in the eastern Caribbean, which departs a few weeks earlier. A recent search for a one-way flight from New York City to Southampton with an Oct. 30 arrival turned up fares starting at $252 on Air India. 866/562-7625, royalcaribbean.com.

Lisbon to Bridgetown, Barbados, Nov. 11-25, 2007. Luxury cruise line Windstar's Wind Surf, which has 154 staterooms and is mainly propelled by seven giant sails, charts the Greek Islands all summer and the Caribbean all winter. A week-long Caribbean voyage in December runs a hefty $1,700 per person for interior cabins, but you can enjoy this two-week transatlantic cruise, which is twice as long, for roughly the same price. A recent search for airfares for one-way flights on Nov. 10 between New York City and Lisbon, the starting point of the cruise, started at $422 on Lufthansa. 800/258-7245; windstarcruises.com.

Rome to Fort Lauderdale, Oct. 5-21, 2007. At the end of its summer season in the Mediterranean Sea, Holland America's Westerdam heads west on a 16-night repositioning cruise to the Caribbean. The ship stops at Monte Carlo, Marseilles, Valencia, Almeria, Ponta Delgada, and the Bahamas. An interior cabin was recently selling for $1,608 per person, or $107 per night. One-way flights to Rome (from Ft. Lauderdale for Oct. 4) recently started at $617 a person (Delta). 877/724-5425, hollandamerica.com.
Contrast that with a shorter, six-night Caribbean cruise departing Oct. 28, 2007, on the Westerdam: The rate for the same room was recently $1,275 a person, or $212 a night, which is roughly double the per-night price of the repositioning cruise.

To find more repositioning cruise itineraries, go to Yahoo's travel page. Look for the "Find it Fast" box at the top, choose the "Cruises" tab, and go to the drop-down menu for "Destinations" and click on the "transatlantic & repositioning cruises" option. Check the websites of individual cruise lines to see each one's full offerings of repositioning cruises, which may include Panama Canal passages.

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