Sitting below a 250-year-old chestnut tree on the terrace behind the Castello di Castagneto Po near Turin, the Italian supermodel-turned- singer, former face of Guess and Versace, is chatting happily about her family’s hilltop estate where she spent much of her childhood and adolescence.

Carla, 37, has often had to fight off the paparazzi because of her relationships with the likes of rockers Mick Jagger and Eric Clapton, and billionaire Donald Trump. But last week she agreed to talk about the castle to help her widowed mother, Marisa Bruni Tedeschi (the family’s full name), launch the first in a series of exhibitions that the family hopes will breathe new life through its ornate halls.

Staring out over the valley of the River Po, Carla talks of the castle as a refuge from her schedule in Paris where she lives, juggling the recording of a new album together with mothering four-year-old Aurélien, her son by her French boyfriend Raphaël Enthoven, a philosophy professor.

Her debut album two years ago, Quelqu’un M’a Dit (Somebody Told Me), was likened to Jane Birkin’s work and sold 1m copies in France. Music runs through her veins: her mother was a concert pianist, her father composed music and was the director of the Teatro Regio, Turin’s historic concert hall, and her grandfather wrote operas.

Carla’s father, Alberto, a wealthy industrialist whose non-musical day job was running the CEAT tyre-making empire, bought the castle in 1952. Built to guard the region of Piedmont from invasion, the castle has died several deaths, but has been resuscitated every time. Since the 11th century, when it is first mentioned in historical records, it was burnt to the ground in 1397, rebuilt, razed once more in 1705, and rebuilt again.

By the time Alberto bought it, the place was a near-wreck, and he spent the next three decades restoring and embellishing it. “There were no bathrooms, just one bath. We left that room half-finished to show what a state it was in then,” Carla says. Alberto put in central heating and built kitchens, bathrooms and lifts. “We put the lifts in 12 years ago,” explains Carla’s mother, “because we thought we were getting on.” Carla chips in:

“Thank God for the lifts! I found the stairs tiring even as a teenager. There are four floors, but the ceilings are very high.”

But it is on the decoration that Alberto lavished most effort. He restored ancient frescoes in the grotesque style, installed rare marquetry parquet, commissioned artisans to craft wood panelling, hung paintings and tapestries. In a nod to an 18th-century fad, he decorated the music room only with Chinese ornaments.

Precious artworks are peppered throughout the reception areas and private apartments, including a medieval crucifix with a life-size Christ and an image of the Virgin by Renaissance sculptor Luca della Robbia.

Alberto was a collector — of china, handkerchiefs, even flags — and to show part of his collection, Marisa has opened to the public for the first time the three main reception halls, where French, English and Italian miniature portraits from the 18th and 19th centuries are displayed. Contemporary artists’ videos from Turin’s Modern Art Gallery are also on show in vaulted rooms below.

Visitors can also see the terraced garden that Alberto fashioned out of the hillside, a soothing panorama of alleys flanked by rose bushes, geraniums and lemon trees next to the castle, and, beyond, lawns, fountains and orchards.

As children, Carla and her two siblings — her sister, Valeria Bruni Tedeschi, the film director and actress, and her brother, Virginio, a graphic artist — lived in Turin but spent holidays and weekends at the castle.

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