1. Forte di San LeoSan Leo The Fortress of San Leo is a castle on the border of the Romagna and Marche; the castle is best known as the site where Count Cagliostro died. It was one of the palaces owned by Federico da Montefeltro and his wife Battista Sforza and was a fortified, palatial retreat. It is now a museum. From Wikipedia, the free encyclopedia.