 The historical center hosts religious and civil colonial buildings, which are noted for their architectural and historical significance and are a rich mix of styles which are rooted in indigenous cultural contributions (mainly from Ute origin), incorporated in the Mozarabic and castizo, and later in modern European influences (mainly French and Italian) and American (specifically, from the United States).Guadalajara's historical center has an excellent assortment of museums, theaters, galleries, libraries, auditoriums and concert halls, particular mention may be made to Hospicio Cabañas (which dates from the 18th century), the Teatro Degollado (considered the oldest opera house in Mexico), the Teatro Galerías and the Teatro Diana.The Hospicio Cabañas, which is home to some of the paintings (murals and easel) by José Clemente Orozco, was declared a World Heritage Site by UNESCO in 1997.