The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

The stones of this Incan wall complex fit together so well you couldn't fit a piece of paper between some of them.

Astronomical observatory above Lake Titicaca.

On the outskirts of a desert trading village high on the Andean plain, steel giants have been destroyed by salt winds.

This hotel is located on the edge of the world's largest salt flat and is made out of the only material around.

This red lake 4,000 meters above sea level is home to rare flamingos.

A series of waterfalls so massive they straddle the border of Argentina and Brazil.

The world's second largest single-dish radio telescope, once used to contact E.T.

The highest peak in Puerto Rico is home to a rare fern that can only be found on six trees at its summit.

An unusual round church in London with a Templar past.

One part local history, 99 parts gruesome haunted house.

A bridge destroyed three times: once as a ruse, then in an actual attack, and finally for the movies.

This museum preserves the hand-dug tunnel that kept Sarajevo afloat during the Serbian siege.

Oriental bazaar in the heart of Sarajevo.

The place where World War I began.

An apparition of Virgin Mary in Herzegovina.

An ancient knight and a symbol of the city's freedom.

Bridge that died in war and was resurected.

A tiny church on a man-made island in the Adriatic.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

A minotaur, a labyrinth, and a dubious restoration pull in visitors from around the world.

The ancient latrines of the Greeks, in all their public glory.

A model village fit for an emperor.

A black cat protests the City Guild in Riga's Old Town.