The area we are interested in, the 'Valle di Follonica', was during the first half of the 14th century an open space outside the city wall circuit until 1416, when it was incorporated into it.
The first mention of the Fountain is found in the oldest Biccherna book that has come down to us and is dated 1226; even then, the Fountain was inscribed with the name 'Fonte di Follonica' and there was talk of an 'ancient' and a 'new' fountain. The Fountain was organised in distinct and communicating rooms. One or more drains brought water to the main basin, located higher up than the second basin, dedicated to watering animals, and finally there was the wash-house. Around the first basin, there are low stone parapets that still clearly show the holes on which the barriers rested to prevent animals from getting close to the drinking water.