South America's answer to Nepal, Bolivia (map) is isolated, undeveloped, and crisscrossed by high-altitude trekking routes.

Its rugged terrain—from the steamy Amazon Basin to 20,000-foot [6,096-meter] Andean peaks—has kept highway builders at bay, leaving vast tracts of forest undisturbed and more than 95 percent of the country's roads unpaved. Five-hundred-year-old Inca trails remain the best links between many isolated communities.

For travelers, the colorful village of Sorata, located in the foothills of the Cordillera Real beneath 20,867-foot [6,360-meter] Nevado Illampu, is the perfect base. Some of Bolivia's best treks and climbs begin right in town, where guides and supplies are easy to find and prices—as they are everywhere in the country—are incredibly low.

All prices in U.S. dollars.

Where to Go
Sorata's winding cobblestone streets and palm-lined town plaza sit at a relatively mild 9,000 feet [2,743 meters], making it easier to acclimatize here than in the 12,000-foot [3,658-meter] capital, La Paz.

While your body adjusts, you can make the 8-mile [13-kilometer] day hike to the Gruta de San Pedro, a deep cave with a swimmable lake, or rent a mountain bike from Café Illampu (about $7 a day) to explore the surrounding hills.

After a few days, most travelers are ready to set out on a longer trek. The best of the many options is the Mapiri Trail. A challenging eight-day walk, it crosses half a dozen 13,000- to 15,000-foot [3,962- to 4572-meter] passes before descending northward from open grasslands into the Amazon Basin cloud forest.

The trail was blazed a century ago by German quinine traders; since then, the forest has swallowed up most signs of humanity, and the lower reaches seem the exclusive domain of maddening swarms of flies, bees, ants, and wasps. Hikers emerge from the void into the tiny village of Mapiri, at an elevation of 2,500 feet [762 meters], where jeeps, buses, and river canoes can take them back to civilization.

Guides from the local Asociación Guías Turísticas Sorata lead hikes on the Mapiri Trail ($125 for small groups); contact the organization through the Residencial Sorata (see Lodging and Food).
 

How to Go
In the high-season months of July and August, the best fares to La Paz are about $800 from New York and $850 from Los Angeles. Fares from Miami are as low as $550.

Hotwire (www.hotwire.com) and Travelocity.com (www.travelocity.com) have consistent bargains, as do consolidators Mena Tours & Travel (800 937 6362 [U.S. and Canada only]; www.menatours.net) and Pino Welcome Travel (800 247 6578 [U.S. and Canada only]; www.pinotravel.com).

For travel within Bolivia, buses are usually the fastest and cheapest option. The four-hour trip to Sorata from La Paz costs $2. From Mapiri, the three-hour canoe ride to the gold-mining town of Guanay is $6.50. Buses leave from there for La Paz, $8 and 12 hours away.
 

Lodging and Food
Clean double rooms in La Paz, Sorata, and other centers can be found for $15 or less.

The most interesting lodging in Sorata is the Residencial Sorata ($10 to $14; +591 811 5044; resorata@ceibo.entelnet.bo), the grand former residence of the same quinine traders who built the Mapiri Trail. Their legacy doesn't extend to the deserted footpath: Bring a tent or rent one from the Sorata guides' association ($16 for the trek).

Mapiri and Guanay both have bare-bones guest houses, or alojamientos, which charge about $2.50 a person. Restaurant meals—even in the traveler-oriented eateries of Sorata—cost about $2 to $3.

Your guide can help you purchase food for the Mapiri trek (he or she is eating it, too); expect to spend $15 per hiker, plus $8 if you need to rent a stove.
 

Visas and Vaccinations
Most visitors can enter Bolivia visa-free for stays of up to 90 days. The main health risks travelers face are altitude sickness, hepatitis, yellow fever, typhoid, and, in the Amazon Basin, malaria.

—McKenzie Funk

Photograph by Aaron Teasdale; map by Seve Walkowiak