photo: Dr. Christos-Nikolas Vittoratos as seen on http://www.8linden.de/historisches.html
The classic functional built-in kitchen dubbed “Frankfurter Küche” was designed by austrian architect Margarete Schütte-Lihotzky. It was built a few thousand times from 1926 onwards in the Frankfurt area. This small (6 sqm), functional and democratic kitchen is seen as the “mother of all built-in kitchens”.
Here is a video about the kitchen: