Shell-Haus, Berlin

In 1929 a competition was held between five architects to determine the designer of a prestigious new office block to house the headquarters of the mineral oil company, and Shell subsidiary, Rhenania-Ossag. The victor was the German architect and professor Emil Fahrenkamp (1885-1966).
After almost two years in construction, Shell-Haus opened in 1932. At the time the building was noted for its modernist design, for its striking wave-like façade, and for being one of the first steel-framed high-rise buildings in Berlin. In retrospect it is regarded as Fahrenkamp’s masterpiece and one of the most significant office block designs of the Weimar Republic.
Shell-Haus’ simplistic graceful forms are stylistically reminiscent of the German modern realist movement New Objectivity, but Fahrenkamp also incorporated more traditional aspects to his design.
The most eye-catching feature of Shell-Haus is its main façade, which jumps forward in six gentle waves whilst at the same time increasing in height from six levels (five at the back) to ten. The building itself comprises four wings situated around a four-sided inner courtyard.

Source: Wiki (EN)