At the foot of the rock of Castel Gandolfo, where the hill gradually slopes down towards the plain and the coast of Anzio and Nettuno, there was a singular extension of cultivated ground. Practically a jewel case of market gardens and orchards gathered in the area of an ancient volcanic crater in which a lake formed.
It was drained in the imperial age; the hydraulic engineers of ancient Rome created a network of trench ducts, still in use today, taking the water to the area from the lake of Castel Gandolfo. They thus obtained the twofold result of replacing a marshy and unhealthy area with a fertile expanse.
The golf course originated here; the eighteen holes were designed respecting the hollow of the crater and inserting fairways in the setting of rich vegetation where century old Mediterranean olives and pines are interspersed with vines, cypresses, mimosas, citrus fruits and rose-gardens. Castelgandolfo is known for being the Pope's summer residence.