Palazzo Giustiniani or the Piccolo Colle is a palace on the Via della Dogana Vecchia and Piazza della Rotonda, in Sant'Eustachio, Rome. The palace contains the official residence of the President of the Senate of the Republic, the Sala Zuccari, the offices of the Life senators and former presidents of Italy, and some administrative offices. From 1901 until 1985, it was also the seat of the Masonic order of the Grand Orient of Italy.