Working staff check the turret of Castello Estense as less visitors seen in the historical city of Ferrara, 68 kilometers northeast to the epicenter of the earthquake in northern Italy, on May 30, 2012. Ferrara, City of the Renaissance, and its Po Delta which was inscribed on the World Heritage List in 1995, were slightly affected in the earthquake with most of the historical sites in the city shut down and protective measures taken by the local authority. (Xinhua/Sun Wen)