Called the "Armenian Stonehenge," this ring of menhirs pierced with holes may be a prehistoric astronomical observatory.

After visiting hours, this picturesque waterfall is essentially turned "off" to be used for hydroelectric power.

For patriotic Russians, this memorial honoring the Soviet soldiers who died liberating Berlin in 1945 is the most sacred location outside of Russia.

This crumbling, graffiti-covered mansion sits tantalizingly within reach of the proletariat who frequent a public park.

A giant snail sculpture looking longingly at the German traffic museum.

The world's oldest known salt mine.

The roof of one of the world’s largest spice markets provides a grand view over the neighborhood's glorious bustle.

Touching this little fossil embedded in the wall of a grand mosque-cathedral may make your wishes come true.

A curious carving hides on a marble column in the Mosque-Cathedral of Córdoba.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

More than half of this Indian palace is drowned but it looks all the more spectacular for it.

27-room home built with the fortune of a sugar magnate.

One of few lasting examples of the brief octagon craze that developed into folly.

A brooding mansion of clinker brick stands out among the Victorian houses of Pacific Heights.

Built in 1906, this unique building was the first Hindu temple in the United States.

The only urban monument in the world designed by the great surrealist painter Salvador Dalí.

This 18th-century sundial was designed to calculate the date of Easter each year.

Legend says this sacred tree was a gift from goddess Athena.

Heralded as the world's first theater, these ruins are often overlooked as they reside in the shadows of the Acropolis.

An ancient octagonal weather station named for the eight Greek gods of wind.

In this Parisian garden's grotesque former life as a zoo it fed exotic animals to the bourgeois and put humans on exhibit.

Ancient barriers wrap around what was once an important stop along the Silk Road.

Monasteries on rock pillars, once accessible only by frayed ropes.

A rare example of a medieval house in Rome adorned with a melancholic inscription.