first prominent constructivist architects to emerge in Moscow was Konstantin Melnikov, the number of working clubs – including Rusakov Workers' Club (1928) – and his own living house, Melnikov House (1929) near Arbat Street in Moscow. Melnikov traveled to Paris in 1925 where he built the Soviet Pavilion for the International Exhibition of Modern Decorative and Industrial Arts in Paris in 1925; it was a highly geometric vertical construction of glass and steel crossed by a diagonal stairway, and crowned with a hammer and sickle. The leading group of constructivist architects, led by Vesnin brothers and Moisei Ginzburg, was publishing the 'Contemporary Architecture' journal. This group created several major constructivist projects in the wake of the First Five Year Plan – including colossal Dnieper Hydroelectric Station (1932) – and made an attempt to start the standardization of living blocks with Ginzburg's Narkomfin building. A number of architects from the pre-Soviet period also took up the constructivist style. The most famous example was Lenin's Mausoleum in Moscow (1924), by Alexey Shchusev (1924) The main centers of constructivist architecture were Moscow and Leningrad; however, during the industrialization many constructivist buildings were erected in provincial cities. The regional industrial centers, including Ekaterinburg, Kharkiv or Ivanovo, were rebuilt in the constructivist manner; some cities, like Magnitogorsk or Zaporizhzhia, were constructed anew (the so-called socgorod, or 'socialist city'). The style fell markedly out of favor in the 1930s, replaced by the more grandiose nationalist styles that Stalin favored. Constructivist architects and even Le Corbusier projects for the new Palace of the Soviets from 1931 to 1933, but the winner was an early Stalinist building in the style termed Postconstructivism. The last major Russian constructivist building, by Boris Iofan, was built for the Paris World Exhibition (1937), where it faced the pavilion of Nazi Germany by Hitler's architect Albert Speer. Modernism becomes a movement: CIAM (1928) By the late 1920s, modernism had become an important movement in Europe. Architecture, which previously had been predominantly national, began to become international. The architects traveled, met each other, and shared ideas. Several modernists, including Le Corbusier, had participated in the competition for the headquarters of the League of Nations in 1927. In the same year, the German Werkbund organized an architectural exposition at the Weissenhof Estate Stuttgart. Seventeen leading modernist architects in Europe were invited to design twenty-one houses; Le Corbusier, and Ludwig Mies van der Rohe played a