We'll happily surrender the beaches to the spring break sunbathers. The real action South of the Border is up in the mountains on singletrack. Dubbed the heart of Mexico, the interior state of Guanajuato is a land of artist colonies, World Heritage sites, and the Sierra Madre Mountains – all connected by trails that are perfect for mountain biking.
You'll need a guide in this mostly unmapped, and, frankly, notoriously volatile region (the Mexican Revolution erupted here, after all). Beyond Boundaries is the only full-service guide in the area. Fortunately, it's also staffed by pros. Over eight days on the Biking Through the Legends of Colonial Mexico Tour, you'll push through 105 miles of trails, splitting time at night between two hubs: the 450-year-old Hacienda Las Trancas, with a winery onsite and a gourmet restaurant dishing up made-from-scratch local favorites; and Hotel Mansión Virreyes, located in the cultural center of San Miguel de Allende.
Trails traverse non-technical backcountry dirt roads as well as rockier paths that follow old silver mining routes through the mountains. Amazingly, past dramatic mountain views and vibrant villages, you won't see another cyclist cross your path the entire time. The relatively new Cannondale hard tails that Beyond Boundaries provides are more than sufficient to tackle the slightly sketchy, loose-rock downhill section of the Camino de la Plata, one of the infamous silver road routes and the hardest trail on the tour.
The most memorable loop starts at the La Gruta Hot Springs, just outside San Miguel. We biked 15 miles of cobblestone west to Atotonilco, where we toured an old Catholic church full of pre-Reformation religious art (read: bloody, torturous), then downed a Caguama: a 32-ounce bottle of Corona-like beer. Back on the bikes, we traversed two hours of doubletrack through the shrubby chaparral, past fields of wildflowers, herds of cattle, cowboys, and cacti – all against the backdrop of the 9,000-foot Sierra Madre. We ended this day with a long soak in the thermal hot springs, one of which was deep inside a cave. Our guide, Alberto "Beto" Martinez, told us that booze always tastes better after biking (we won't argue). He proved it with a bottle of Jaral de Berrio, made from 100 percent pure maguey, a variety of agave that has grown naturally in the region for centuries. [$2,599, all-inclusive; bikebeyondboundaries.com]