Climb at Hueco Tanks, TX
About 32 miles northeast of El Paso, Hueco Tanks is sun country—and positively pleasant in December, when the granite cliffs and boulders attract climbers in flocks. The area is particularly well-known for its preponderance of challenging boulder problems. Nearby, Hueco Rock Ranch, which offers camping, is a de facto climber hangout. On rest days, check out some of the hundreds of human, animal, and mythological drawings left by Native Americans in the area.

Ski Jay Peak, VT
Further north than many of Vermont's big-name resorts like Stowe and Killington, Jay Peak sometimes flies under the radar of snowsports enthusiasts. But the mountain is in a honey hole for weather and doesn't uncommonly see sizeable snow dumps in December. And since it's close to the Canadian border, you'll likely have the 2,153 vertical feet and 76 trails, including some of the East Coast's hairiest chutes and glades, to yourself.

Surf the North Shore of Oahu, HI
Notorious breaks like Mavericks and Pipeline give the North Shore of Oahu a fearsome reputation. With plenty of sandy beaches and a variety of breaks, however, this hub and birthplace of the sport has just as much to offer beginner and intermediate surfers. Pick up tips by watching surf greats like Andy Irons and Kelly Slater, who show up in December for the last competition in the Vans Triple Crown of Surfing, the Pipeline Masters.

Fish in Alabama's Fresh and Salt Water
The weather in Alabama in December and January is a roll of the dice, but the benefit of the mercury dipping below 60 degrees is that local anglers run for cover. All the better for northerly visitors: This is prime trophy bass season and the Alabama Bass Trail offers options from Joe Wheeler State Park to Lake Guntersville. Further south, the sun-soused Mobile-Tensaw Delta and the Gulf Coast offer saltwater fishing for winter refugees.

Backcountry Ski the Wallowas, OR
Instead of a series of volcanoes typical of Oregon, the glaciated Wallowas more resemble the Rockies, with steep fall lines and a relatively dry snowpack. Translation: The Eagle Cap Wilderness has some of the state's best—and least frequented—terrain, with nary a lift in sight. Slap skins on your skis and trek 6.6 miles to the Aneroid Lake cabins, the perfect base camp for endless yo-yos and sublime solitude. One caveat: the backcountry and inexperience don't mix. Hook up with Wing Ski (800.646.9050; www.wingski.com) and do it right.

Scuba Dive in the Cayman Islands
It's hard to find reasons not to go to the Cayman Islands in December—balmy weather; calm, clear waters; and the Cayman Islands Jazz Fest, which usually falls early in the month, to name a few. Divers have long flocked here for the reefs, abundant sea life, shipwrecks, and visibility that can reach 200 feet. Spend daylight in search of undersea creatures at dive sites like Stingray City. Come evening, search out beats and brews.

Cruise, Cross-Country Ski, and Kayak in Antarctica
Discovering the earth's southernmost continent used to involve days on end sequestered on a giant ship with precious little time on the ice. Now, expeditions cater to the more antsy traveler, offering camping, cross-country skiing, and kayaking excursions with eye-popping, up-close views of the landscape's intricacies—ice formations, penguins, and migratory birds like Wilson's storm petrel. Hook up with Quark Expeditions (203.656.0499; www.quarkexpeditions.com) to do it right—they run all varieties of active-centric cruises to the region.

Explore Ethiopia
Walking through Ethiopia is like standing in scenes from the Bible—watch as white-cloaked men wander about the rock-hewn churches of Lalibela or the tombs, palace ruins, and obelisks of Axum. In December, southern Ethiopia hosts a giant music and dance festival and Christmas brings country-wide public celebrations. Interspersed between these cultural attractions are a trove of natural wonders, from the caves at Sof Omar to the Simien Mountains and the hot springs of the Awash River lowlands.

Ski Bansko in Bulgaria
Despite the fact that skiing history runs deep in Bulgaria's mountain hamlets, foreign ski fanatics have only recently discovered the country's snowy slopes. And in the last few years, Bulgaria's well-known resort, Bansko, which has wide-open peak terrain reminiscent of the Alps, has seen all manner of improvements. Now, lively hotels and restaurants stand next to centuries-old pubs and town squares. By mid-December, the snow is already deep enough for boundless turns.

Trekking the Cape to Cape Track in Australia
The Cape to Cape Track, between Cape Naturaliste and Cape Leeuwin, is about three hours south of Perth on one of the most remote swaths of coastline on the planet. The schlep there is rewarded with wildflower meadows, plunging seaside cliffs, and sparkling empty beaches—sans even an inkling of a crowd. On the way there or back, hit the burg of Margaret River, a wine-making hub.