Ancient serpentine sacrifice holder that has stood the test of time.

A fountain standing as a testament to a doomed alliance.

An Art Nouveau gem hides beneath the layers of city grime obscuring this once-magnificent building.

Five sultans and their families rest in eternal splendor, teeming with overlooked beauty and drama.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

A marvel of Byzantine engineering under the streets of Istanbul.

A small etching on the white marble parapet was written in runic script by a Viking mercenary.

Roman ruins, natural methane fires and a lovely beach.

This arch granting triumphal entrance into Antalya was designed to honor the emperor's visit.

This incredible stone temple is a monument to death, victory, and fantasy architecture.

One of the most iconic neon ads of former East Germany.

Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.

This 16th-century pole was once used in brutal public executions.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

This unmarked and unloved Manhattan subway grate created one of the most iconic images in American cinema.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

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

Did Inca children also slide down these smooth rocky slopes above Cusco?

Built on the remains of one the Incas’ most important gathering spots, this square keeps the spirit of a fallen empire alive.

Situated on a sacred Inca site, this 16th-century cathedral took nearly 100 years to build.

A painting in the historic Cathedral Basilica depicts Jesus and his disciples dining on a traditional Peruvian menu.

An extensive network of secret tunnels was created for the Nazi project "Riese."

A fairytale Gothic castle steeped in Nazi treasure conspiracy theories.