The forbidden atoll: With a dark past of sex and murder, Zannone is the wildest atoll of Rome's Pontine archipelago. The isle is the location of Marquis Casati Stampa's former vacation retreat.
courtesy Parco Circeo-Marco Buonocore
Zannone: The island's notoriety began when a chic but sexually adventurous aristocratic couple rented the isle from the state during the 1960s.
courtesy Parco Circeo-Marco Buonocore
'Sex parties isle': The colonial villa was where Marquis Casati Stampa's lavish sex parties took place. Residents living nearby say the debauched get-togethers were an open secret.
courtesy Corpo Forestale Stato
Murdered actress: Anna Fallarino, the wife of the Marquis Casati Stampa, was murdered by her husband on Zannone.
Pier Mario Fasanotti, "Kriminal Tango"
The marquis: "He was a lewd man, a voyeur who liked to watch and photograph his starlet wife get kinky having sex with with other younger guys," says Giorgio Aniello, who runs boat tours to Zannone.
courtesy Turist casa Cristina de Paoli
Spies in the house of love: Rumor has it the villa also featured a "hidden mirror room" to spy on sex sessions.
courtesy Valerie Romano
Wild parties: Yachts and motorboats would land at weekends bringing dukes, barons, countesses VIPs and billionaires. "The villa was a hot jet-society get-together," recalls former caretaker Salvatore Pagano.
courtesy Valerie Romano
Peaceful and isolated today: Today, there's nothing on Zannone but the abandoned villa and a lighthouse.
courtesy Parco Circeo-Marco Buonocore
Lush island: The 102-hectare Zannone is part of the Circeo National Park. Visitors don't need a permit, but only biologists, scientists and bird watchers are allowed to camp the night.
courtesy Ponza Racconta
Entering Zannone: For visitors, it's a short swim between the boat and the private pebble beach once used by Anna Fallarino.
Silvia Marchetti/CNN
Entrance to villa: The hike to the marquis's house is tough. The villa, built within the grounds of a medieval monastery, sits on Zannone's highest peak.
courtesy Corpo Forestale Stato
Rugged coast: The island, surrounded by emerald-green waters, is a maze of reddish-yellow cliffs, old stone fisheries and crooked sea stacks.
courtesy Corpo Forestale Stato
Sole inhabitants: Introduced to the island by Italian aristocracy to make hunting more fun, mouflons -- wild sheep with big curly horns -- are now Zannone's only permanent inhabitants.
courtesy IAT Latina
Alternative tourist attraction: After the tragedy, the mansion was shut and the isle was returned to the state. Now visitors come to explore the "forbidden atoll" and its dark history.