4 Best Sights in The Southern Andes and Lake Titicaca, Peru

Flying overhead, you can't miss the green, fertile trough as it cuts through the barren terrain, but it's all an illusion; only scrub brush and cactus cling to the canyon's sheer basalt sides and miles of ancient terraces. The canyon is named for the stone warehouses (colcas) used to store grain by an ancient culture that lived along the walls of the gorge.

Carved into the foothills of the snow-covered Andes and sliced by the silvery Río Colca, Colca Canyon is 3,182 meters (10,440 feet) deep. The more adventurous can embark on a hike into the canyon—typically a two-, three-, or five-day excursion. Bird lovers (and anyone with a penchant for amazement) can visit the Cruz del Condor, currently home to 38-odd animals. Culture seekers can spend a night with a native family. Light hikers and archaeology aficionados can observe points along the rim, and those seeking pure relaxation can hit one of the all-inclusive lodges that offer horseback riding and thermal baths.

Colca Canyon may be the region's most famous natural attraction, but at 3,354 meters (11,001 feet), Cotahuasi is the world's deepest gorge, beating Colca Canyon by 163 meters (534 feet). It's nearly twice as deep as the Grand Canyon. The canyon has been carved by the Río Cotahuasi, which becomes the Río Ocuña before connecting to the Pacific. Its deepest point is at Ninochaco, below the quaint administrative capital of Quechualla and accessible only by kayak. Kayak explorations first documented the area in the mid-1990s and measured its depth. Since then, paddling the Cotahuasi River's Class V rapids is to kayakers what scaling Mount Everest is to mountaineers.

The ride from Arequipa to the Cotahuasi Canyon ranks with the great scenic roads of the world. As you pass Corire and Toro Muerto, the road rides the western side of snowcapped Nevado Coropuno (6,424 meters, 21,076 feet), Peru's third-highest mountain, for spectacular views as you descend into the valley of Cotahuasi. Logistically speaking, it's a bumpy 11- to 13-hour bus ride or 10 hours by four-wheel drive from Arequipa. The pavement ends in Chuquibamba after about five hours of driving, and then resumes for the last hour of the drive, between the Mirador of Cotahuasi as you descend down to the canyon. There is no fee to enter.

Cruz del Condor is a haunt for the giant birds, particularly at dawn, when they soar on the thermal currents rising from the deep valley. At 1,200 meters (3,937 feet), the "condor cross" precipice, between the villages of Pinchollo and Cabanaconde, is the best place to spot them.

From June to August, you're likely to see close to 20 or more condors during a morning visit.

By October and November, many of the female birds are nesting, so your chances of eyeing flocks are slim, though you'll likely spot a few birds. It is possible to take a taxi or bus to the Cruz del Condor from Chivay, but if you take a tour from there, your guide will likely only speak Spanish. If you want a guided tour in English, you will need to set this up with a tour operator ahead of time in Arequipa or Cusco. If you overnight in Cabanaconde or Chivay, you can also visit the Mirador before the sun sets. It's when the condors return to their nests, and you'll have the place all to yourself.

Below the village of Cotahuasi is the valley of Piro, the gateway to the canyon, which is close to this 150-meter-high (492-foot), three-tiered, 10-meter-wide (33-foot) waterfall. Sipia Falls is the most-visited attraction in the entire canyon.