León's showpiece Museo de Arte Contemporáneo has been acclaimed for the 37 shades of coloured glass that adorn the facade; they were gleaned from the pixelisation of a fragment of one of the stained-glass windows in León's cathedral. Within the museum is one of Spain's most dynamic artistic spaces. The airy galleries mostly display temporary exhibitions of cutting-edge Spanish and international photography, video installations and other similar forms; it also has a growing permanent collection. Concerts are held here regularly.