It's an ingenious, gravity-fed system that links the Atlantic and Pacific oceans via three sets of locks that raise ships 85 feet from sea level to Lake Gatun and then back down. For ships that fit through the 950-foot locks, aka Panamax ships, the 48-mile canal eliminates the often perilous, 8,000-mile journey around the southern tip of South America.
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Cruisers—at least those who get up early to beat their shipmates—get a front-row seat to the action, in which locomotive "mules" nudge ships into place, the gates swing shut and the chambers are filled or partially drained. From ocean to ocean, transit typically takes 8–10 hours.
For Al and Sunny Lockwood of Cotati, California, transiting the canal was the highlight of a 17-day cruise between San Francisco and Fort Lauderdale two years ago. As Sunny tells it, the trip came about by accident—a car crash, actually, in which a texting driver ran into them while they sat at a red light.
"It dawned on us that we could've been killed and that we better start doing some of things we've always dreamed of doing," said Sunny. "My husband is a retired engineer and at the top of his bucket list was the Panama Canal."
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Such one-way sailings are often offered in the spring and fall as the cruise lines reposition ships between Alaska, the Caribbean and other seasonal destinations. "You can do the Western Caribbean, the canal and [Mexico's] Western Riviera, so it's like combining three itineraries into one," said Chiron.
Other cruisers opt for so-called partial transits, which are typically shorter roundtrip sailings from Florida that pass through the Gatun Locks and into Lake Gatun before sailing back out to the Caribbean.
Between the two options, the major cruise lines offer around 75 sailings per year through the canal (plus an additional 60 itineraries that are part of even longer sailings). Norwegian Cruise Line, for example, offers 20 sailings—nine roundtrips from Miami, 11 repositioning—plus an extra eight on sailings of 26 days or more.
"Our Panama Canal cruises are so popular with our guests that we've added another roundtrip itinerary from Miami for the 2015/2016 winter season on Norwegian Pearl," said Vanessa Lane Picariello, director of public relations.
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And there may even be more sailings to come as work continues on a third set of locks that will be able to handle larger, so-called post-Panamax ships. It's too early for the cruise lines to make any commitments—the new locks are scheduled to open in December 2015—but Picariello does offer a tantalizing hint of what could come.