A fantastic telephone system has been developed just for the 1920s Berlin Project!
It works just like a real phone, you have to pick up and talk into the horn, what you say comes out on the other side of the line!
You can come try it by using the public pay phones.
From now on you can also buy one for your own home if you are a tenant.
They are great fun and a great tool for roleplay.
You can order your own phone from the poster at the Post office on Alexanderplatz.