Lazing on a beach or contemplating museum displays is all right, but some travelers crave a little more action. The Yucatán has plenty to offer active, outdoorsy travelers, including sports such as scuba diving and kiteboarding, and activities such as bird-watching and snorkeling with whale sharks. This tour is a workout for the eyes, too, taking you to some of the peninsula’s most stunning (and little-visited) natural areas, from deserted windswept shores to tangled mangrove forests to limestone caverns filled with the clearest, bluest water you’ve ever seen.
Arrive in Cancún  but plan on basing yourself along the Riviera Maya . Playa del Carmen  and Akumal  have the most lodging ptions, but are by no means the only choices. If you’re planning on diving, consider heading straight to Isla Cozumel  to save yourself the ferry ride tomorrow.
Spend your first full day exploring the Riviera Maya . You’ve got plenty of options: for divers, there’s no shortage of world-class diving at Isla Cozumel . You can book two-tank dive trips on the island or at dive shops at Playa del Carmen. Or try cenote diving on the mainland; shops in Playa del Carmen and Tulum have the most experience, or you can head to Hidden Worlds  or Dos Ojos, both of which offer full-service guided dive trips at privately managed cavern systems. You also can snorkel at any of the previously mentioned places, as well as on the coral reef at Puerto Morelos  or at Laguna Yal-Ku  in Akumal.
Get up early and head straight to Chiquilá to catch the ferry to Isla Holbox . Leave your car in one of several lots near the ferry pier.
Go snorkeling with whale sharks  in the morning and kayaking through the mangroves in the afternoon—the bird-watching is excellent here. Or just go snorkeling, and take some time after lunch to relax on the island’s rustic beach. If you know how to kiteboard, rent equipment for the afternoon; if you don’t, learning the basics usually takes about three days.
Return to Chiquilá and drive to Mérida . If you get an early start, you may have time to stop over at the beautiful colonial town of Izamal  or the cenotes of Cuzamá , where a horse-drawn cart takes you through abandoned henequen fields to ladders that lead into underground caverns for a cool swim.
Drive to Celestún  and take a flamingo tour . You can get there on your own or book a tour at one of Mérida’s many tour operators. Head back to Mérida and check out a museum and one of the nightly cultural performances.
Spend the next day visiting some of the grutas (caves) along the Puuc Route  south of Mérida. Calcehtok  is the most adventuresome, with local guides offering two- to five-hour tours of this huge cave system. The longest tours go about four kilometers (2.5 miles) and reach a tiny chamber where human bones were left from ancient Maya ceremonies. Not far away, Loltún caves  have paths and lighting, but are fascinating nonetheless. Drive to Valladolid .
Get up bright and early to be at the entrance of Cobá Archaeological Zone  by 7 a.m., or earlier. Of all the nearby Maya ruins, this one is the best for bird-watching. It’s not uncommon to spot toucans and parrots, among many other species. Cobá is also an impressive ancient ruin, with the second-highest pyramid in the Yucatán Peninsula, affording awesome views of the countryside. The structures are set in a thick forest—hence the first-rate bird-watching—and are quite spread out. You can rent bikes near the entrance and explore the ruins on wheels, also unique among the Maya ruins. There’s a monkey park a short distance from Cobá, a great place to see howler and spider monkeys. Treat yourself to a night at one of the beach cabañas in Tulum.
Spend your last day enjoying the Yucatán’s other great natural wonder: the beach. Tulum  has the best of the best—white sand lapped by turquoise water and backed by palm trees. Hey, even eco-adventurers can use some sand time. If you get restless, rent some snorkel gear and check out some of the cenotes  near Tulum village.