Millions of sun-seeking Americans flock to the Caribbean every year for its welcoming sands and warm waters (its proximity to the mainland doesn't hurt either). But those who venture to the islands mostly arrive by cruise ship, touring the harbors with such brevity that they rarely experience anything beyond the main tourist spots. Even if you only have a limited amount of time in port, there's plenty to see and do to make the most of your short stopover. Next time your ship pulls into harbor, use this guide to plan your island adventure.See: Best Places to Visit in the CaribbeanThe crystal blue-green waters of the West Indies are one of the biggest draws to the region, which makes it ideal for snorkeling. There are a bevy of tour companies that will take you for a boat ride off the coast to a location full of vibrant and picturesque underwater wildlife. In the British Virgin Islands, you can snorkel from your boat to the outer islands and explore The Baths in Virgin Gorda. From there, you can hike the caves to Devil's Bay and immerse yourself in the legendary tales of the area's pirates and the treasures they once stashed here.The best part? You can see all of this in about three to four hours. You'll want to pack plenty of sunscreen and a waterproof camera, because the views under the sea and through the caves will be worth the selfies.Flying in a chartered plane or signing up for a helicopter tour will allow you to understand the gravity of the Caribbean's beauty. But if you want to get a bird's perspective, get to the highest point of the island and jump on a zip line tour. In the British Virgin Islands, for example, the Original Virgin Canopy Tours in Tortola starts in the hills at the top of Johnsons Ghut. On the tour, you'll sail through the rainforest canopy, enjoying views overlooking the south coast and Road Town, with lush vegetation and tropical birds surrounding you. On clear days you can even spot St. Croix in the distance. Bring a sports camera like a GoPro to document the whole adventure.See: Best Cruise Lines in the CaribbeanUse one island as a base and visit one, two, three or more islands that are within easy reach. If your budget allows, there are plenty of small airlines that offer reasonable rates for these quick adventures. St. Martin is a great example of a destination that offers a central airport and easy ferry access to St. Barts, Anguilla and Saba — the "Unspoiled Queen of the Caribbean."From the British Virgin Islands, board a flight to Anegada to see the only coral island in the volcanic chain. It's 11 miles long with its highest point measuring just 28 feet. Among other superlatives, it's home to the Horseshoe Reef — one of the largest coral reefs in the world. When you're not discovering the reef's underwater maze of sunken ships, try your hand at other watersports like kite surfing and stand-up paddleboarding.Keep in mind: These excursions can take up an entire day of your itinerary. And since they are secluded adventures (Anegada is the most sparsely populated of the British Virgin Islands), you'll want to prepare your meals in advance, either by preordering food from island restaurants or packing your own.Many consider mangroves the smelly, swampy areas of the islands. But they are an important part of the ecological system as they provide nutrients and shelter for juvenile species. As such, exploring mangroves are great for up-close encounters with nature. On Beef Island at the Surfsong Villa Resort, you can take a tour by kayak or stand-up paddleboard that will start you off on the calm, peaceful flat water behind the secluded property. The vegetation is so plush and healthy that you can see everything from exotic birds to sea snakes to nurse sharks.To complete your journey on this two-hour tour, you must cross through the ocean and around the sharp and jagged coral, which will crank up your adventure trip beyond your imagination. But it's recommended that you know how to swim (as you may fall off your paddleboard and into the open water). You can also request a life vest from your guide.See: Best Hotels in the CaribbeanAbout the author: Dayvee Sutton is a two-time Emmy Award-winning journalist, public speaker and entrepreneur. She is the founder of www.daily-affair.com, where she and her team write about lifestyle topics. Follow @dayveesutton on Facebook, Twitter and Instagram.