A fifth-century temple improbably built into the side of a cliff.

A tiny piece of the Moon is embedded in this stained glass masterpiece.

A four story, football field-sized, nine-grotto creation made of shells, minerals, and rare stones.

This single room has survived the centuries with almost no deterioration.

The Avenue of Mausolea is a series of grand palatial tombs.

Giant marble phalluses on the sacred island of antiquity.

The palace of the King of Kings, burned by Alexander the Great.

Resonant stone, that has been played since prehistoric times.

Ozymandias’ time-keeping temple.

The hallucinogenic center of the ancient world.

The oldest surviving synagogue in New York City is now a soaring art space.

One of Europe's largest supercomputers is housed inside of a disused chapel.

This futuristically sylvan church is a glass-enclosed marvel of modern architecture.

A restored Pittsburgh house of God has been converted to a marvelous house of suds.

This centuries-old gothic monster has been converted into a sprawling, glossy bookstore.

This centuries-old Italian chapel hangs midway down a sheer cliffside.

One of Frank Lloyd Wright's final works was this UFO church.

Take a stroll through the hellish grotesques of Hieronymus Bosch in this elaborate Netherlands church.

This tiny church near Sleepy Hollow contains Henri Matisse's last work, a rose window, and nine windows by Marc Chagall.

A geological oddity topped with a 2,000-year-old pagan temple.

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

The largest earthwork effigy in the world.

A Swedenborgian glass church surrounded by redwoods sits perched atop a massive landslide area.

A set of ancient drawings in the desert of Peru that are so massive, many of them can only be fully seen from the sky.