Ecuador may not have the world's highest mountains, but thanks to the accessibility of the country's big peaks and its supply of experienced, bilingual climbing guides, it is one of the great mountaineering destinations. The country's popularity among climbers has grown steadily since the British mountaineer Edward Whymper -- the first to ascend many of Ecuador's mountains -- chronicled his experiences in an 1892 book called Travels Amongst the Great Andes of the Equator. But you don't need to read Whymper to be inspired enough to want to climb one of Ecuador's massive snowcapped volcanoes, which dominate the landscape in much of the northern Sierra.

The country's highest peaks are divided between eastern and western cordilleras that flank a fertile central valley, known as the "Avenue of the Volcanoes." The view from the summit of one of those mountains on a clear morning is truly breathtaking -- if you've got any breath left to take after making the climb. But even a hike to the edge of one of their glaciers, or an ascent that fails to reach the summit, can provide an unforgettable experience.

Ecuador has peaks that are technically difficult enough to challenge experienced climbers, but it is also an excellent place for an introduction to the sport, thanks to the existence of various mountaineering schools. Because the country's second highest peak, Cotopaxi, is a relatively young, conical volcano, it presents a technically simple climb that is accessible to climbers with various levels of experience. If you're in good shape and acclimate quickly, it is feasible for you to take an introductory course and end up climbing Cotopaxi within a week's time.

Whether you are an experienced climber or a mountaineering novice, safety is always the priority, which means climbing only with trained, experienced guides. The popularity of the sport has resulted in an over-abundance of companies offering climbing tours, many of which are of dubious quality. The minimum training your guide should have is that required for membership in ASEGUIM, the Ecuadorean Mountain Guides Association; it's preferable, though, that a guide has had some training abroad as well. That said, there is no substitute for experience, so if you are going to attempt an ascent of a big peak, make sure your guide has climbed it at least a dozen times.

The most popular peaks have large refuges at their bases with kitchen facilities and rooms full of bunks, where climbers hit the sack early in order to start their ascent around midnight. Climbing outfitters reserve bunks, provide transportation, and take care of dinner. Serious climbers will want to pick up a copy of the book Climbing and Hiking in Ecuador, by Rob Rachowiecki, Mark Thurber, and Betsy Wagenhouser.

The Big Peaks

Climbers have dozens of mountains to choose from in Ecuador, but most head up the same peaks, especially the two highest -- Chimborazo and Cotopaxi -- which may be ascended by several groups at once during the driest months. Here are the biggest and most popular peaks:

Chimborazo (6,310m/20,702 ft.) This massive glacier-encrusted peak, 150km (93 miles) south of Quito, has five summits, the highest of which is named for Whymper, who believed it was the tallest mountain in the world when he ascended it in 1880. It has claimed the lives of many climbers and requires experience and acclimation. Best weather: June to January.

Cotopaxi (5,897m/19,347 ft.) A perfectly conical, snowcapped volcano less than an hour south of Quito, Ecuador's second-highest mountain is also its most popular climb. Though technically straightforward, the ascent demands good physical conditioning, ice axes, crampons, and ropes. It can be climbed year-round, but the best weather is in December, January, and July to September.

Cayambe (5,790m/18,996 ft.) Ecuador's third-highest peak, this extinct volcano north of Quito is climbed less frequently than Cotopaxi because it has crevasses and suffers from more inclement weather and avalanches. Nevertheless, qualified mountain guides regularly lead successful ascents there. Best weather: July and August.

Antisana (5,704m/18,714 ft.) Ecuador's fourth-highest peak, Antisana towers over the eastern edge of the Andes, which means it is more influenced by Amazon-basin weather. The surrounding scenery of lakes and forest and the abundance of Andean condors make this a good area for hikers -- but the frequent clouds and crevasses near the summit make it a difficult peak to climb. Best weather: December and January.

El Altar (5,319m/17,451 ft.) This massive, extinct volcano with nine summits is a challenging technical climb complicated by frequent inclement weather, but even if you don't make the summit, you'll enjoy the impressive scenery on the lower slopes. Best weather: December to May.

Tungurahua (5,023m/16,480 ft.) Located within Sangay National Park, remote Tungurahua is an active volcano that was part of the climbing circuit for years when it was dormant, but massive eruptions in 2006 knocked it off the circuit, at least for the time being.

Mountaineering Outfitters

Adventure Planet Ecuador (tel. 02/2863-086; www.adventureplanet-ecuador.com) offers guided ascents of the country's highest peaks and mountaineering tours that range from to a 6-day "soft climbing" package to a 3-week tour that combines ascents of five volcanoes with a rainforest trip.

Climb Ecuador (tel. 212/362-4721 in the U.S.; www.climbecuador.com) is a New York-based mountaineering outfitter run by mountain guide Roger Kovary; they use experienced local guides who have passed various mountain-rescue and first-aid courses. You have a choice of 2-week packages for experienced climbers that combine ascents of four summits with acclimation hikes and other activities.

Compañía de Guías de Montaña (tel. 02/2901-551; www.companiadeguias.com.ec), started by a group of Ecuadorean climbing guides 17 years ago, offers guided ascents of most of the country's big mountains and 9- to 15-day packages that combine acclimation and ascents of several summits with general sightseeing.

Ecuadorian Alpine Institute (tel. 02/2565-465; www.volcanoclimbing.com), a local climbing and trekking outfitter, organizes ascents for experienced climbers and offers mountaineering training for beginners and intermediate climbers.

International Mountain Climbing School (tel. 603/356-7064 in the U.S.; www.ime-usa.com), based in New Hampshire, organizes annual climbing tours to Ecuador.

Moggely Climbing (tel. 02/2906-656; www.moggely.com), a European-owned Ecuadorean outfitter, offers guided ascents of the country's principal peaks for very competitive prices, without cutting corners on safety. They also have 1-day glacier-climbing courses.

Safari Ecuador (tel. 02/2222-505; www.safari.com.ec) organizes ascents of the country's main climbing peaks and runs Andes Climbing School, which offers an introduction to the sport and acclimatization programs.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.