Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

Picturesque intersection of witchcraft and ancient Christianity.

A hidden three-foot-wide house separates these two regal churches.

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

This giant sculpture made of trash is a critique of society's wastefulness.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

One of the smallest bookstores on the planet.

Catacombs turned marketplace.

The haunting concrete remains of a Nazi pebble crusher can still be found in this small French commune.

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.

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

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

"Holy Wisdom" overlooks the city that became its namesake.

Sofia's legislative center is continuously reinventing itself.

A magnificent, glittering building tucked into a tiny Bulgarian mountain town.

This ancient theater, restored in the 20th century, lives on as a venue for dramatic and musical performances.

A striking symbol of the Bulgarian capital.

An abandoned saucer-shaped monument in the Bulgarian mountains.

This city square is home to Amsterdam's oldest church and a statue honoring Dutch sex workers.

This unattributed sculpture in Amsterdam is hiding in plain sight.

This 22-floor tower's Skydeck offers panoramic views of Amsterdam.

This World War I fortress is the perfect place to catch a Montenegrin sunset.

A tiny church on a man-made island in the Adriatic.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.