The Chapel of St. James bears most impressive witness to the past splendor of Vicovaro. Built by Giovanni Antonio Orsini to hold the family tombs, it was situated on one of the most important Orsini properties.
The Chapel faces the Church of St. Peter. It has an octagonal floor plan and an elaborate portal on the side facing the square which gives it an elegant, sumptuous look.
The lower part is late Gothic with a Northern air, designed by Domenico da Capodistria. It has twenty four niches, framed by pediments, pinnacles, wimbergs and columns, which hold twenty four free-standing statues of saints.
The upper part is formed of a typically Renaissance sculpture ensemble: fake niches with bas reliefs of the fathers of the church and the evangelists, two tondi with the Archangel Gabriel and Our Lady of the Annunciation and a lunette, set in an archivolt of angels welcoming the Virgin and Child with St. Peter and St. Paul to each side who are presenting Napoleon and Roberto Orsini, brothers of the Archbishop Giovanni Orsini and masters of the Marsicana territories.
The elaborate façade also holds a tympanum, with two winged cherubs holding the family crest in the pediment.
The interior was reorganized in 1700, with the painting of the Praying Virgin by Giacomo Triga, a painter of the Roman school and member of the Academy of St. Lucae, on the altar of the Chapel and an oval of the Eternal Father by the painter Salvatore Monosilio dating to 1752.