Art Nouveau architecture was popular in Riga, the capital of Latvia, in late 19th century and the beginning of 20th century - about 40% of the buildings from this time period were built in this style. Several substyles formed during this period. Early on elements of the new style were added to Eclectic architecture forming "Eclectic" Art Noveau. "Decorative" Art Noveau refers to style making use only of decorative elements of the Art Noveau, first such building was built in 1899, however by 1906 decorative styles had become unfashionable. Therefore the decorative style is not very widespread in Riga. Most popular style in Riga is known as "Romantic" Art Noveau - simplistic and modern in form, these buildings were decorated with elements from other historic styles and constitute about one third of all buildings in the central Riga. From 1905-1911 Latvian National Romantism peaked - while being a substyle of Art Noveau it attempted to copy forms of traditional architecture and incorporated traditional decorative elements. As the Art Noveau matured emphisis on vertical lines became more popular, known as "Vertical" Art Noveau this style was most popular shortly before the WWI. The center of Riga is now designated as UNESCO World Heritage site in part for its Art Noveau architecture.