Zannone is one of the five islands of the Pontine Marshes. To date is part of the Circeo National Park and in order to be visited by land you need a permit which can be applied to municipality.
On the island as well as a pristine flora you can see the mouflon, a protected species, and several species of migratory birds such as the peregrine falcon and the swamp falcon. Through the trails you can join in with the ruins of a Cistercian monastery (Mount Pellegrino area) and a headlight (area Cape Negro)