The Fonte dell’Abbondanza (Fountain of Abundance) is made up of three pointed arches that precede as many tanks, which once contained water. The structure had two main functions: it was used as the town’s main water supply and the upper floor (built in the 15th century) was used as a warehouse for harvesting cereals. But the feature that makes this Fountain unique is the very modern and profane fresco visible on the left facade, called "Tree of Fertility", which has survived to our days thanks to the thin layer of limestone that covered it. It is believed that originally also the other internal walls were painted but unfortunately the restoration works carried out so far have been able to bring to light only traces of frescoes. The peculiarity of the painting lies in the subject represented: a large tree with phallic fruits is the background to what seems to be a public feast, where a group of women in the foreground try to grab the fruits hanging from the branches. The fresco, therefore, should be interpreted as a propitiatory hymn to life.
Currently, the tanks are empty, so that the fresco can be preserved in the best possible way, and the upper floor is used as a multipurpose room that hosts exhibitions, conferences and film screenings during the year. In April 2019, during further restoration, a new fresco dating back to the 13th century was brought to light, depicting a woman holding two beasts with chains and warriors protecting the access tunnel of the water table. On the sides we can distinguish, even if incomplete, two figures of animals protecting the burrow: on the right a lion and on the left presumably a bear. A mermaid with two tails dominates the upper lunette.
