Here’s a terrific poster, from the 1920s, for the Mitropa long-haul services across Europe.
Mitropa began as a specialist railway catering company in Germany during WW1. The war provided for an enormous expansion of railway services to support the German military effort. The firm effectively took over the German parts of the Wagons Lits services.
After WW2, the firm became a staple of travel across the Soviet bloc of countries.
Since the 2000s, the company has focussed on platform services and has become part of the Compass Group.