Starting at Prato della Valle, one of Europe's largest squares, you'll open the Explorial app, enter the 6-digit game code that you received by text and Viator chat message, and get moving. The tour is fully self-guided — no guide, no fixed start time, just your group and the city. At the Tomba di Antenore, a 13th-century canopy tomb on a busy corner, the app asks what locals debated for centuries: does it really hold the Trojan prince who founded the city? At Palazzo del Bo, seat of Padova's 800-year-old university, clues circle the courtyard where Galileo taught and where Europe's first permanent anatomy theatre was built. Then the domes and spires of the Basilica di Sant'Antonio rise ahead — a Byzantine-Gothic mashup sheltering the tomb of St. Anthony, with riddles waiting on the square outside. Around 2 hours at a relaxed pace, spritz breaks allowed. By the end, Padova's mix of science and sainthood will have won you over.