One of the most important examples of medieval Italian sculpture. Built to commemorate the completion of the new aqueduct between 1278 and 1280 by Nicola and Giovanni Pisano, the design was by Fra Bevignate, and the hydraulic project by Boninsegna da Venezia. It is made up of two concentric polygonal basins, mounted on a bronze basin topped with statues of three female figures. The lower basin features bas-reliefs of the twelve months of the year, accompanied by the signs of the zodiac and other allegorical symbols. The upper basin is made up of twenty-four panels divided by religious and allegorical figures.

In a complex iconographic message, the decorations of the fountain, “one of the most powerful expressions of life in medieval times” (Walter Binni), bring alive the political and cultural lifestyle of the Municipality of Perugia, with representations of universal knowledge and the history of humanity, as well as the celebration of Perugia, its legendary foundation and its role in the area.

Lower basin - Each panel is marked out by a small spiral column, and then divided into two parts by another little column. 24 bas-relief panels represent mankind’s various trades through the months of the year and the signs of the zodiac. There are also representations of the lion and griffin of Perugia, the seven liberal Arts, Philosophy, episodes from the Old Testament (Adam and Eve and the Expulsion from Eden), stories of Samson, David, Romulus and Remus, and some of Aesop’s fables.

Upper basin - Resting on little columns, it is characterized by smooth mirrors, except for one facing Palazzo dei Priori, with an inscription in gothic letters commemorating the restoration of the aqueduct in 1322. Along both the basin’s upper edge and base, are two more inscriptions giving details of the work and its authors. In the angles between the mirrors are 24 small statues, representing the symbols of Perugia, Trasimeno and Chiusi, as well as saints and characters from the Old Testament and Perugian history.

The bowl - The bronze bowl is the work of Rosso Padellaio, a Perugian metal caster (1277). It is topped by a bronze statue of three nymphs carrying an urn from which water spurts. 

Near the fountain is a 47-metre deep well of Etruscan-Roman origins, (though the well is indicated as medieval), which provided the town’s water.