Visit the Palazzo Pubblico

The largest surviving Romanesque church in Europe, built for pilgrims on the road to Santiago and topped by a five-tier octagonal bell tower.

Paris’s 850-year-old Gothic cathedral, reopened after the 2019 fire with its spire and oak roof rebuilt by hand.

Beijing's vast imperial palace complex.

The oldest of San Marino’s three towers, an 11th-century fortress on Monte Titano with views to the Adriatic.

Second tower on Monte Titano’s highest summit, home to the ancient-arms museum.

Visit Cologne Cathedral, a masterpiece of High Gothic architecture and a UNESCO World Heritage site. Construction began in 1248 and took over 600 years to complete. It is the tallest twin-spired church in the world, standing at 157 meters, and houses the Shrine of the Three Kings, a reliquary said to contain the bones of the Biblical Magi.

Gaudi’s hillside park of mosaic dragons, twisted stone colonnades and a serpentine bench overlooking Barcelona.

Gaudi’s dragon-backed house on Passeig de Gracia — bone-like balconies, a scaled roof and not a straight line inside.