The rail museum Thielenbruch was established by the Historische Straßenbahn Köln e.V. (i.e. the association Historic Tramway Cologne). In this museum, you can see more than 20 tramways, a model railway, historical props of the Cologne tramway, and technical objects (e.g. an old signal box wall, and a historical city map). For children, there are two vehicles on which they can become tram drivers themselves, and they can also try their hand at lifting a scissor pantograph.
Within the museum, you will also find snacks such as pancakes and coffee. Outside of the museum, there is the Swabian restaurant Aubele’s Restaurant am Straßenbahn-Museum Köln where you can eat, for instance, one of my favorite German dishes: Käsespätzle with ham and fried onions. Close by, there is stage 8 of the Kölnpfad (a 171km trail that goes around Cologne).
The museum is open every second Sunday of the month, and you will find members of the association there who can answer any questions you may have. Entrance to the museum costs €1 for children, €1.5 for adults and, for an additional €5, you can take a virtual journey through time.