Starting at Brüdergasse 8 in the old town, you'll open the Explorial app, enter the 6-digit game code that you received by text and Viator chat message, and follow Bonn's compact centre. The tour is fully self-guided — no guide, no fixed start time, just your group and the city. The Beethoven-Haus opens on a high note — the pink townhouse where Ludwig van was born in 1770. Riddles play through prodigy years and famous scowls. The Bonner Münster follows, five towers of Romanesque gravity built over the graves of two Roman martyrs whose giant stone heads lie outside. Trivia investigates. Then the Kurfürstliches Schloss stretches its baroque wings — once the electors' palace, now the university's main building, with the Hofgarten lawn out front. Around two hours through the city that ran West Germany for forty years. The leaderboard decides the final movement — fortissimo.