Pietro Bernini, father of Gian Lorenzo, designed the characteristic fountain, commissioned by Pope Urban VIII Barberini. Stories tell that Bernini was inspired by an old boat beached during the overflowing of the river Tiber in 1598. It was constructed at ground level to compensate the low pressure of the acqueduct of the Acque Vergine at that time. It was decorated on the inside by two Barberini " sun mouths" sprouting water out in a fan. Two coats-of-arms of Urban VIII may be seen externally. Some irony may be noted, knowing that this type of boat was usually used for the transportation of wine.