Anatural spring used by man since prehistoric times, Fonte Grande (‘Large Spring’)—or Fonte Maggiore (‘Major Spring’)—has been the major water reserve for the inhabitants of the walled town of Mondolfo. Its use dates back to the Eneolithic Age, as documented by various finds now housed in the local Civic Museum, and continued throughout the Roman era and the Middle Ages. In 1526, the municipal authorities decided to build a wash trough and have been responsible for its conservation ever since, along with the access roads and paths. In 1776, the community entrusted technician Francesco Polinori to draw up a global maintenance plan for the area, in order to renovate the water collection systems and redesign the site. His efforts yielded that masterly yet functional water distribution system which we can still admire today.