Latvia has been a member of UNESCO since 1991. Some of Latvia's UNESCO recognized sites include the historic center of Riga, which contains old Riga and art nouveau architecture. Another is the Cabinet of Folksongs, which contains over 200,000 pieces of handwritten Latvian folk songs and texts. A third is the Latvian Song and Dance Celebration, a large festival held every five years featuring thousands of performers of choirs, dances, and bands.