The director of the Bauhaus, Walter Gropius, built a private residence for the married couple Anna and Felix Auerbach in Jena in 1924. The building, which consists of two intersecting cuboids, is the first practical realization of his idea of a building block on a large scale. The clearly structured, smoothly plastered façade is also characteristic. The colorful interior was designed by Alfred Arndt. It consists of 37 pastel shades, which were discovered during the restoration and painstakingly reconstructed based on original findings.