VENICE, ITALY – March 9 2018 A visitor takes a picture on one of the paintings at the exibition ”John Ruskin Le pietre di Venezia” during the press preview at Palazzo Ducale on March 09, 2018 in Venice, Italy. The Exhibition ‘John Ruskin Le pietre di Venezia’ will stay open until 10th June 2018 at Palazzo Ducale in Venice.