Op-art architecture designed for happiness.

This one-time health resort was used by aristocrats around the world.

Switzerland's oldest public observatory is an important part of the Zurich cityscape.

Go inside to really appreciate this 500-year-old technological masterpiece.

This underground tunnel system built during World War I offers a fascinating glimpse into Pula's military history.

This exclusive resort has completely covered a tiny Balkan island in a 5-star warren of guest rooms.

According to a local legend, this old castle could only be built after a woman was immured in the walls.

Feast on coconut crab curry at one of Thailand’s only outposts of Baba cuisine.

Eat the ultimate iteration of Portugal's most beloved pastry.

This once-forgotten oasis in the middle of Lisbon was first created over a century ago quite by accident.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

The first green space constructed on an elevated viaduct.

The industrial architecture honors the laborers who brought the Exposition Universelle of 1900 to life.

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

Daily jousts and dancing barrel makers in Munich's mechanical clock.

Go surfing on this urban wave, "hacked" by local surfers.

Walk inside a half mile long crevice right outside the town of Garmisch Partenkirchen.

A beautiful gorge filled with streams and waterfalls.

A unique bridge with an equally unique view.

The fairy tale castle of the “fairy-tale king,” this was also the inspiration for Disney’s “Sleeping Beauty.”

A favorite with sightseers and locals alike, this Norwegian funicular provides easy access to a stunning view of Bergen and its environs.

Watch a magnificent, ever-changing colorscape inside James Turrell's immersive work of art.

Walk behind a 50-meter-high waterfall.

A living museum working to keep the traditions of building and repairing handmade wooden boats, ropemaking, and blacksmithing alive.