The bizarre floating Uros Islands of Lake Titicaca in Peru and Bolivia started appearing long before the Inca began carving stone cities. People known as the Uros fled their enemies, creating islands from reeds and grass and floating to safety in hidden corners of the lake.
Philip Bloom
Almost 100 man-made Uros Islands float near the shores of Lake Titicaca. The lake sits at an elevation of over 12,000 feet -- twice as high as Denver.
Philip Bloom
Some of the more modern islands accommodate tourists, but many of the Uros people still live in extreme poverty, squatting in a Peruvian nature reserve in Lake Titicaca.
Philip Bloom
Inca ruins top Isla Del Sol, or Island of the Sun, a large island in the Bolivian sector of Lake Titicaca. The Inca built these structures without tools at an elevation higher than where skydivers typically jump out of planes.
Philip Bloom
There's no way to drive to Peru's Machu Picchu. Visitors either hike for days on the Inca Trail or ride a train that snakes its way through the Andes along the Urubamba River.
Philip Bloom
A train pulls into the station at Aguas Calientes, Peru, the gateway to Machu Picchu. More than a million tourists descend upon the spectacular Inca ruins of Machu Picchu each year.
Philip Bloom
That's about 3,000 visitors each day. Archaeologists worry about the impact of tourism on the ruins. Long before Columbus set sail, the Inca built an empire with a reach as big as two Californias.
Bill Weir
The ruins of Pisac are closer to Cusco, the historic capital of the Inca Empire. Increased awareness of the less-crowded ruins surrounding Cusco could help relieve some of the tourism pressure on Machu Picchu.
Philip Bloom
On the outskirts of Cusco, the ruins of Saqsaywaman feature a central ring that was once the five-story Temple of the Sun with a gold-lined ceiling etched with constellations of the night sky.