The Art Nouveau period in Riga coincided with an upswing in industry, trade and culture. Early 20th century was a time of unprecedented construction boom. Art Nouveau buildings make up almost one third of the entire built-up area in the city centre. In the early 20th century, around 50 architects were active in Riga. Most of them were of local German-Baltic descent. Only 10 architects were Latvians, but they were responsible for more than 1/3 of all buildings constructed then. The Art Nouveau of Riga is versatile in its formal expressions yet from the very beginning it was mostly rational and even modest and reserved. Such is also one of the first Art Nouveau buildings in Riga, apartment house with shops at Audēju iela 7 (1899, architects Alfred Aschenkampff and Max Scherwinsky). A number of earliest monuments of Art Nouveau in Riga presents romantically artistic trend of Art Nouveau. Among examples of this stylistic trend is apartment house at Alberta iela 12 (1903, architect Konstantīns Pēkšēns). Now, it contains the Riga Art Nouveau Museum. When Art Nouveau just started to flourish, the new style was often perceived only as a change of a decorative outfit of buildings, replacing retrospective eclectic elements with new trendy ornamental motifs that were already well developed in other visual arts at that time. Such examples of Eclectically Decorative Art Nouveau in Riga are several early works of architects H. Scheel and F. Scheffel, of K. Pēkšēns, Rudolph Heinrich Zirkwitz, A. Schmaeling, J. Alksnis, Karl Johan Felsko, August Witte and others. About a dozen of buildings of Eclectically Decorative Art Nouveau the façades of which literally bedazzle with abundance of tangles of unusual decorative elements were created by civil engineer Mikhail Eisenstein. Five of them line the Alberta iela. Around 1907, the façades of the newly constructed houses started to display pronounced verticality and slender upright elements of architectural composition. This trend – Perpendicular Art Nouveau became one of the most widespread varieties of the style in Riga’s architecture. The architect Jānis Alksnis made Perpendicular Art Nouveau a trademark of his work. Other architects having been most prolific in this manner are K. Pēkšēns, Eižens Laube, Oskars Bārs, Rudolph Dohnberhg, Edgar Friesendorff, Bernhard Bielenstein, Paul Mandelstamm, Ernests Polis etc. National Romanticism is one of the most peculiar and attractive stylistic varieties among the formal trends of Art Nouveau. In Riga, National Romanticism prevailed for a relatively short period, i.e. only between 1905 and 1911. Nevertheless, it remained as the most splendid episode in the history of architecture reflecting identity of the nation. The most characteristic samples of National Romanticism are buildings designed by K. Pēkšēns, E. Laube, Aleksandrs Vanags, Pauls Kampe and Augusts Malvess. Several German Baltic architects practicing in Riga also contributed to Latvian National Romanticism producing designs in this stylistic manner. Around 1910, there was a tendency to give preference to classical expression in architecture. It was Neoclassicism that emerged as a counterbalance to the excessive use of decorative elements in Art Nouveau. The apartment house with shops at Miera iela 5, built in 1912 to the design by Alexander Schmaeling, Edgar Hartmann and Viktor Unverhau, is a unique architectural gem of Art Nouveau. The massing of the building with its emphasized ribbon-like fenestration very closely resembles typical examples of Modern Movement which emerged only in the 1920s–30s. It is a clear proof that all contemporary architecture actually derives from Art Nouveau.