The starting point is the Berliner Fernsehturm, and from the tower the route drops into the old heart of Berlin. It runs past the Neptunbrunnen, through the lanes of the Nikolaiviertel and across the water to Berlin Cathedral. This is a murder mystery walking tour that you run yourself, at the speed you choose.

Berlin is a wide city, but this route stays inside a small part of it, so the walking between clues remains manageable for families with children, groups of friends, couples and colleagues, and it can be done solo as well. Up to four players form a team around a single phone, and bigger parties split into more teams. No guide comes along and no start time is fixed, which helps on pavements as busy as these.

How to play

Four steps, and you are on the case in Berlin.

1. Book the City Game
2. Check the instructions email
3. Download the Loquiz app
4. Start playing whenever you like

The murder of Balthasar is the case in hand. You crack codes, take photographs where the game asks for them, and hear out digital characters whose statements rarely agree. The Altes Museum and the Friedrichsbrücke both appear on the trail, and each solved puzzle takes another suspect out of the running.

With two or more teams out at the same time the whole thing becomes a race, which is what makes it usable for teambuilding as well as for a free afternoon. Pause for coffee, take the trail up again, and settle the case in the middle of Berlin whenever you please.