Below are portfolios with photos of Art Nouveau buildings.
Art Nouveau of Brussels
18 buildings, mostly private residences, from 1893 to 1911
Vienna Secession
39 major and minor Secessionist buildings from different parts of Vienna (1894-1914)
Budapest Secession
118 structures from between 1888 and 1918 (all notable Secessionist buildings in Budapest); some tombs and museum pieces (including stained-glass windows and mosaics)
Trieste Secession (Liberty)
39 public and private buildings from between 1901 and 1914
Zagreb Secession
13 buildings from between 1898 and 1913
Sarajevo Secession
10 buildings from between 1903 and 1913
Timișoara Secession
38 buildings from between 1900 and 1914
Lviv Secession
41 buildings, including five examples of the Hutsul Secession, mostly from the mid-1900s
Madrid Modernism
10 buildings, more than a half of them private dwellings, from between 1902 and 1923
Las Palmas Modernism
15 buildings in Triana and Vegueta from between 1899 and 1923
Malta Art Nouveau
24 buildings from the 1910s to the 1930s; mostly villas and townhouses
Istanbul Art Nouveau
29 buildings in Beyoğlu and other districts of Istanbul, most from the first decade of the 20th century
Art Nouveau of Riga
59 buildings of Eclectic, Perpendicular, National Romantic, and Neoclassical Art Nouveau (from each year between 1899 and 1913); Art Nouveau interiors and furniture (Riga Art Nouveau Museum)
Modern Style in Tbilisi
56 buildings from between 1902 and 1915, the date of construction and architect of many unknown