Colegiata y Universidad de Osuna Monument · Osuna, Sierra Sur, Seville The Colegiata de Nuestra Señora de la Asunción was founded in 1535 and the ducal pantheon was built between 1544 and 1555. The 16th-century University of Osuna operated until the 19th century and is today declared a Bien de Interés Cultural by a 2004 decree. 1535 (fundación de la Colegiata); 1544-1555 (panteón ducal); 2004 (declaración BIC de la Universidad) Photo: Antonio M. Romero Dorado (Public domain) What to see and do in Osuna