Guglielmo Boccanegra had Palazzo San Giorgio built in 1260 as a civil and political base to counterbalance the increasing power of the clergy at the nearby cathedral. After his exile two years later the palazzo began a series of identity changes. It has been just about everything, from the first town hall to a prison (Marco Polo was held captive and dictated his memoirs there from 1298-1299 after the Genoese victory over his native Venice), to a bank (Banco di San Giorgio, possibly the world’s first bank in 1407 and still up and running today). Nowadays it is the HQ for Genoa’s Port Authority and was, for a long time, the base for the city’s sea trade and customs. You need to phone first if you want to visit inside. If not, enjoy the garish frescoes of Saint George killing the dragon from the outside.