A marvel of Byzantine engineering under the streets of Istanbul.

This crucial gathering spot along the "hippie trail" still displays old notes between traveling beatniks and backpackers.

Legend says if you stick your thumb in the hole and it gets wet, your wish will be granted.

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

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

A fountain standing as a testament to a doomed alliance.

The trials and tribulations of marking Poe’s grave.

Tour the dark and beloved poet's former cobwebbed basement, which may have inspired "The Black Cat."

The hallucinogenic center of the ancient world.

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

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

These secluded and abandoned anti-aircraft defenses have become one the most scenic viewpoints in Barcelona.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Barça football fans might see the insignia hidden in a church window as a divine sign.

A former steam-powered mill from the 1800s is now an industrial park with a giant steel dragon slide.

An architect transformed this abandoned cement factory into his castle-like workshop.

A science fiction-inspired apartment building designed by a famous Spanish architect.

Construction of Barcelona’s iconic (but controversial) church was finally completed in 2026—a century after the death of its architect.

Men in rubber-soled boots serve as your "brakes" on this toboggan ride Hemingway described as "exhilarating."

These small, triangular, colorful houses are a staple of Madeira Island.

The inspiration for the Patagonia Clothing logo, Cerro Fitz Roy turns pink at sunrise.

This stunning mass of ice spans 121 square miles and is still growing.

The most southern point you can drive to in the Western Hemisphere.

This plaza at the end of the world teems with monumental tributes to a problematic history, and laser discs.