The `` Monumento dei quattro mori '' ( `` Monument of the Four Turks '' ) , dedicated to Grand Duke Ferdinando I de ' Medici of Tuscany , is one of the most important monuments of Livorno . The `` Monumento dei quattro mori '' ( `` Monument of the Four Moors '' ) , dedicated to Grand Duke Ferdinando I de ' Medici of Tuscany , is one of the most important monuments of Livorno .