The wild expanses, nature reserves, hideaway beach clubs and ancient sites of the untrammelled Tuscan Maremma

It was Marella’s grandfather, then her environmentalist father, Nicola Caracciolo, and her uncle Carlo, the charismatic and elegant late cofounder of La Repubblica newspaper and L’Espresso magazine, who “discovered” this unsung corner of southern Maremma in the early 1960s. In their wake came friends: left-leaning journalists, intellectuals, emerging conservationists, trailblazers and family such as their sister Marella Agnelli, accompanied by Saint Phalle, with whom she had a warm connection from their modelling days in New York. Saint Phalle brought her dreams to life there: a cluster of fantastical giant psychedelic tarot sculptures in which she set up home. Her bedroom was in one of the vivid mirrored mosaic breasts of the sphinx-like Empress, which rises 50 feet above the olive groves; her kitchen was in the other. This joyous, Gaudí-esque sculpture garden is now a major attraction, inspiring shows at Hauser & Wirth in Somerset last year and recently at Grand Palais in Paris, as well as powering Maremma’s buoyant art scene, spawning studios and galleries in the vicinity. This includes Hypermaremma, the summer art festival on and around the neighbouring Terre di Sacra estate. The event engages artists whose installations reinterpret nature and offer fresh perspectives on this raw, fragile terroir, which the younger Marella, as vice president of the Maremma section of Italia Nostra, the country’s oldest environmentalist association, is determined to protect.

Terre di Sacra was the first estate in the country to eschew the profits offered by hunting, and it hosted the World Wildlife Fund on part of its land in 1967. The vast, semiwild expanse of about 2,500 acres, today with 7.5 miles of rugged coastline, was an anomaly at the time. Here are the breeding grounds and migratory flight paths for some 300 bird species, including flamingo, marsh harrier and heron. One of the pleasures of staying at a rental villa here, such as Cottage dell’Alloro, with its breezy, convivial open-ranch-style simplicity, are the views that give onto brackish Lake Burano, with the dunes and sea beyond, and the dynamic aerobatics of bird colonies.

It’s a bucolic idyll, with rabbits running rampant and wild boar rustling. Peaceful too, despite being near the same railway track I arrived on. The distant rumble of the train runs through this Maremma story, the Genoa-Grosseto-Rome line being indirectly responsible for bringing the estate into existence. In 1922, nobleman Uberto Resta Pallavicino found himself stranded here after a signal failure. During his layover, beguiled by the aqueous light and the wild beauty of the coastal strip, he determined he would gather a consortium of 20 like-minded friends from around Italy to buy up parcels of land. Thus Terre di Sacra was born; until recently known only to the insiders of Rome and Milan as a fashionable weekend escape, a refuge for friends of friends.