Starting at the tourist office by the Porta da Vila, you'll open the Explorial app, enter the 6-digit game code that you received by text and Viator chat message, and enter through the azulejo-lined town gate. The tour is fully self-guided — no guide, no fixed start time, just your group and the city. The Castelo de Óbidos crowns the walls ahead — the fortress a king gave his queen as a wedding present, starting a 600-year royal tradition. Riddles inspect the dowry. At the Pelourinho, trivia decodes the carved pillory bearing a queen's emblem and a fishing net with a story worth hearing. Then the Livraria de Santiago turns a church into a book lovers' sanctuary, shelves rising where altars stood. Around two hours inside the walls, with ginjinha in chocolate cups as the local reward. The leaderboard crowns Óbidos' new monarch.