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

A marvel of Byzantine engineering under the streets of Istanbul.

A sprawling collection of books and manuscripts about ancient Greece that would have put their famed libraries to shame.

The Cycladic architecture makes this Athens neighborhood feel like an island paradise hidden in the shadow of the Acropolis.

These ancient artifacts are a testament to the enduring significance of the bull in Spanish culture.

This enigmatic artifact is a rare depiction of an ancient Iberian noblewoman.

Inside this church are the alleged remains of the patron saint of lovers, epileptics, and beekeepers.

A vault of safe-deposit boxes in an old bank has been repurposed as a time capsule of Hispanic culture.

An iconic and controversial ancient Iberian funerary urn with a hauntingly penetrating gaze.

Among the oldest structures in Madrid, these Moorish walls once guarded the medieval city of Mayrit.

An ancient Egyptian temple in the middle of Madrid, Spain.

This amazing example of Valencian Art Nouveau looks more like a cathedral than a public market.

Of the many chalices in the running for the Holy Grail, this one in Valencia Cathedral sure looks the part.

This massive fiberglass Gulliver turns every visitor into a Lilliputian.

These official units of measurement—including chains and perches—lie hidden beneath tourists' feet in a popular London hub.

This one has sailed five times as far as Sir Francis Drake's famous ship.

London's last remaining public soapbox site has seen speeches from Karl Marx, Vladmir Lenin, and George Orwell.

Scattered throughout London are ancient remnants of the city's former bounding wall.

The remains of Crystal Palace Great Exhibition of 1851.

An unusual round church in London with a Templar past.

This picturesque horseshoe weir was first built in the 1600s to prevent flooding in the town of Bath.

Place with alleged mystical powers in Old Orthodox Church in Sarajevo.

Celebrated example of Ottoman architecture that also served as a site for brutal massacres.

This historic cemetery was inaccessible for several years due to dozens of land mines.