The church of the religious complex, commissioned and financed by Robert I of Anjou and his devout wife Sancia of Aragon (this was how Sancia manifested her repressed vocation to the cloistered life), was built in 1310 by Gagliardo Primario and connected to a monastery of Clarisse, and was destined to house the remains of the Angevin dynasty and, from the 18th century, also those of the Bourbons. After restoration following damage during World War II, only a little remains of the Baroque work Domenico Vaccaro did in 1742. The façade is adorned only by a huge rose window and flanked on the left by the bell tower (which only retains the lower part of the original). Inside, the Gothic style is immediately recognisable. The single nave has ten chapels along the walls with works from the 14th and 15th centuries. Behind the altar, the apse is replaced by a wall (on which rests the sepulchre of Robert of Anjou), pulled up to divide the rooms for the monks from those for the nuns. In fact, on the other side is the choir of the Clarisse, visible only through a grille and designed by Leonardo di Vito as an autonomous three-aisled church accessed through the sacristy. One of the greatest examples of gothic in Naples, the choir contains fragments of a fresco of the Crucifixion by Giotto, who was called to Naples by Robert of Anjou in 1326. The main monuments are the Angevin royal tombs: the tomb of Mary of Durazzo, those of Charles of Calabria, his second wife Mary of Valois and their little daughter Mary.
The courtyard on the left side of the church leads to the cloister of the Clarisse in which the frivolous Rococo style that Domenico Vaccaro wanted to give it is immediately visible: Gothic arches on small columns, a festive garden divided into four sectors by the intersection of two avenues. Secular and devoid of any sacred images is the polychrome majolica decoration by Joseph and Donato Massa (30,000 were used). The colours are those found in nature: the yellow and orange of the citrus fruits growing between the pillars (64 octagonal columns) on which the pergolas rest, the blue of the sky, the green of the vine. Scenes from everyday life are depicted on the backs of the seats. The covered corridors surrounding the cloister preserve 17th-century frescoes with Franciscan stories.