Sophie de Marbois-Lebrun was born in Philadelphia in 1785, the daughter of a French consul, and she married into Napoleon's inner circle. Her husband, Charles-Francois Lebrun, served as Napoleon's arch-treasurer and carried the title Duc de Plaisance. But Sophie's heart drifted east, toward a country fighting for its freedom. She and her daughter Caroline-Elisa threw themselves behind the Greek cause, funding the revolution of 1821 with the fortune at their command. After separating from her husband, Sophie settled in Greece for good. Her money bought enormous tracts of Athens and the surrounding Attic countryside, especially around Penteli, where she raised no fewer than six palaces and houses. She had become, in effect, a one-woman patron of a young nation, building it stone by quarried stone.

Then her daughter died. Caroline-Elisa, her companion in every cause, was gone, and Sophie could not let her go. She had the body embalmed and kept near her. The Rododafni castle was conceived as the daughter's final resting place, a marble crypt dressed up as a summer home. Construction began in 1840 using stone from the famous Pentelic quarries that had once supplied the Parthenon. Greek tradition long credited the architect Stamatios Kleanthis with the design, but the historian Olga Fountoulaki uncovered the real hand behind it: the Frenchman Andre Couchaud, who gave the building its rare neo-Gothic silhouette. In a Greece obsessed with reviving its own classical past, a French duchess was raising pointed arches and Gothic Revival fantasy on the slopes of a mountain Athena's builders had quarried millennia before.

Sophie never finished it. She died in 1854, and the buildings of Penteli stood roofless, their windows open to the sky. According to her friend, the French writer Edmond About, this was no accident of money or time. A superstition had taken hold of the duchess: she believed she would die the moment one of her houses was completed. So she left them deliberately unfinished, each open beam a small bargain with death. It did not save her. After she was gone, her nephew sold the estate, and ownership passed to the Greek state. For more than a century the castle simply decayed, a Gothic ruin on a Greek mountain, its rosetree name fading into legend.

The story did not end in ruin. In 1959 the Greek state began restoring the castle with public funds, and the architect Alexandros Baltzatis completed the work in 1961. For a few years it served an unexpected purpose, becoming a country house for the royal family. The future King Constantine II used it from 1961 until 1964. Today the marble belongs to the municipality of Penteli, which has made the duchess's unfinished dream into something she might have approved of: a cultural center and library, a place for concerts and gatherings of up to a thousand people. The grief that built it has softened into a stage for living. The rosetree, at last, has room to bloom.