Mosaic at Sant'Adriano of a snake wrapped three times around itself and whose body (the flakes made with small triangular tiles) creates three nodes. Mosaic art flourished in the Byzantine Empire from the 6th to the 15th centuries; that tradition was adopted by the Norman kingdom in Sicily in the 12th century, by eastern-influenced Venice, and among the Rus in Ukraine. A mosaic is a piece of art or image made from the assemblage of small pieces of colored glass, stone, or other materials. It is often used in decorative art or as interior decoration. The church of Sant'Adriano (built circa 1000 AD) is a fine example of early Norman-Byzantine architecture and contains some exquisite mosaics and other ancient artifacts. San Demetrio Corone is a town and municipality in the province of Cosenza in the Calabria region of southern Italy.