The Fountain of St. Augustine collects water from two springs and is one of the major attractions of the park. The water is never lacking even in periods of prolonged drought. Monsignor Luigi Biraghi already mentioned this fountain in 1854, when he wrote that it was a habitual place of popular devotion. In fact, in the nineteenth century and throughout the twentieth century, the people of the town paid great attention to this place, recognizing that it was somehow linked to Augustine.
The fountain has a rectangular shape with a lateral hemicycle (maybe two originally). It was probably rebuilt on a previous structure. Currently there remains a remnant that denotes characters of Roman construction. The function of this basin in the past is not known. Its position was, however, close to the medieval castle of which we have news in 1200: the town of Cassago was already inhabited in the ninth century as evidenced by a parchment of 854 which attests to the presence of Lombard nobles as lords of the castle. On the structure of the Fountain have been performed several times both to highlight the foundations and to waterproof the walls.
