Nature reigns here, and nowhere is that more breathtakingly apparent than the Na Pali Coast, where verdant cliffs hide secret waterfalls, unreachable by car or even on foot. That's why you'll be arriving by air.

Here, a remote, unspoiled valley harbors a happy and healthy population of elephants, lions, giraffes, and hippos under the hot African sun. On this particular trip, you'll get major bang for your buck and more profound animal-viewing, because for much of it, you'll be (safely) on foot.

Visiting this less-explored region is like going back in time. It's a fairy-tale landscape of pristine lakes and mazelike waterways, small farms, fields of bluebells, ancient monasteries, deserted beaches, and forgotten castles, one of which can be yours to play house in.

This is truly untamed territory -- one of our country's last great frontiers. An epic way to embrace it is by nestling into a cozy, secluded lodge where everything the majestic state is known for lies right outside your front door.

Every aspect of the world's largest jungle is utterly mesmerizing: Technicolor flora, tribal villages, and animals straight out of Dr. Seuss's wildest fantasies (two words: pink dolphins). The coolest part? You'll be floating right through the heart of it all.

With countless beaches and waters so clear you can see every grain of sand on the sea floor, these sunny, welcoming enclaves are without question an idyllic setting. But to gain VIP access to a whole world of hidden coves and uninhabited islets, charter a boat.

The Maya believed that mysterious cenotes, ancient sinkholes scattered throughout the region, were an entryway into the underworld. Find out what really lies beneath by pulling on a mask and fins and slipping into the water.

Bolivia? Yes, Bolivia. It's home to the largest salt plains on the globe, a high-altitude region of immense flatness that looks gorgeously lunar. Think of this adventure as a safari of mind-blowing landscapes, complete with a knowledgeable guide to help you find your way.

This emerald-blue bay is as postcard-worthy as it gets. Dramatic limestone karsts topped by a veil of lush green vegetation jut out of the ocean, and the only sign of life is the occasional gang of scampering monkeys. The primates are just one surprise; the others are revealed by kayak.