Diving Caribbean reefs, hiking Alaskan glaciers, touring historic European cities — cruises get you places. And all cruise lines offer shore excursions to help you make the most of your time in the ports of call. But which ones are really worth the money? Here are some cases where a shore excursion might be your best bet:

Which cruise shore excursion is the best match for you? — Photo by Image Source/Getty Images

1. Venturing Far From the Port of Call
If you want to see something well beyond the port — say, the Mayan ruins of Tulum from Cozumel, a trip that requires a ferry to the mainland and a bus ride — it makes sense to book an organized excursion. Booking your tour directly with a company can definitely be cheaper and less crowded, but remember you’ll be working with local transportation and schedules, and if you miss the ship's departure, it’s big bucks to get to the next port on your own.

2. Getting Your Blood Pumping
Book a shore excursion when you want to go kayaking in the Sea of Cortez or zip-lining through a Costa Rican jungle. Equipment is provided in these and countless other activities (snorkeling, diving, biking, ATVing, etc), and the cruise line has vetted the local operator for quality and safety, so you can be assured you're not going off with just anybody. Before booking, however, check that the level of activity involved is right for you.

3. Exploring Cultural History
Some shore excursions really do provide a hands-on local experience: say, a visit to a French vineyard to help pick grapes and taste the product. Cooking classes, art lessons, private visits to museums, even folk-dance performances serve up unique cultures and a chance to mingle with locals you can't get on your own.

4. Having an Adventure
Book a "bucket list" experience, the kind of extravagant excursion you'll be telling the folks at home about. Swimming with dolphins in Mexico, dog sledding in Alaska, helicoptering in Hawaii, deep-sea fishing in the South Pacific — all of these adventures provide memories that will last a lifetime, and are almost always worth the money.

5. Kicking Back and Relaxing
Visits to secluded beaches, scenic sails with rum liberally flowing (and maybe even a lobster lunch), romantic catamaran cruises — these shore excursions are all designed to remind you why you took a cruise in the first place — to sit back and relax.

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