Fendi created her foundation, which aims to break down barriers between art, theater, literature, music, and performance, after the fashion powerhouse established by her parents was sold to luxury-goods group LVMH in 2001. The organization has mounted many provocative, avant-garde happenings in its previous home, at the Palazzo Roccagiovine, above the Forum of Trajan, and at other locations in Rome. In this new setting, which Nouvel describes as an “artists’ village,” Fendi also initiated a partnership to exhibit work loaned by the Hermitage Museum.

In addition to galleries and shops, which will open at a later date, the building houses a 24-suite hotel, operated by Spanish hotelier Kike Sarasola, called the Rooms of Rome, and a rooftop branch of Paris’s Caviar Kaspia restaurant, with terraces offering dazzling views of ancient Rome. “It’s a neighborhood under one roof,” says Fendi. “A place for living with art.”

Since the facades are listed as landmarks, Nouvel preserved many elements while giving the building a “new lease of life that is electrifying,” he says. Inside, the architect added steel framing for lintels, pillars, and stairs. For the hotel rooms, he had more leeway to express himself; each apartment, he says, “is a separate project.” While he retained many original fragments of tile and mottled stone, the architect inserted stainless-steel blocks containing kitchens and bathrooms to function as sleek objects in space. Contrasts don’t stop: the interiors of the movable window screens are covered with photo prints showing what the apartments looked like before the renovation began, and new furnishings encompass a variety of custom items as well as highlights of Italian design, such as Castiglioni lights.

Visiting or staying in the Rhinoceros, you feel steeped in antiquity while belonging to the moment—an invigorating and inspiring experience. Says Nouvel, “It’s a play of encounters, a collision of epochs from the most ancient to the most modern.”

Photographic images on movable window screens show glimpses of the apartments before the renovation.