This extravagantly decorated clandestine church built centuries ago when Catholicism was considered a crime is hidden in plain sight behind an unassuming front door in the city centre. Those walking down Juffrouw Idastraat would never imagine that within one of the typical terraced houses lies the enormous Parish of Saints James and Augustine where Catholics used to practice their faith in secret. Nobody is quite sure who built the church, but the stunning baroque plastering seems to suggest that it was the famous architect and artist Daniel Marot or one of his students. Book a free tour which takes you through the church and the attic to the more recent Bishop’s Chamber which is full of some of the original features and furniture that were used in the 1700s.

The Roman city of Emona (1st to 5th century) comprised a large portion of the present-day centre of Ljubljana. Today, enthusiasts can visit the well-preserved section of the southern city wall and two archaeological parks. Items from the Roman era are also exhibited at the City Museum of Ljubljana and the National Museum of Slovenia.

Siena still runs on medieval time—in the best way. Its centre hasn’t changed much in centuries, and that’s part of the charm. The Piazza del Campo is the heart of it all—it’s where the Palio horse race happens twice a year. Climb the Torre del Mangia for wide views across the rooftops. The cathedral’s worth the time, especially its black-and-white striped interior, detailed floor mosaics (open seasonally), and the Piccolomini Library tucked inside. Don’t skip the crypt or the Museo dell’Opera del Duomo—they’re quieter and give you a different angle on the city.