Sant'Angelo was constructed in the mid-16th century by the Spanish general and Governor Milan Ferrante Gonzaga, over an edifice already existing in 1418, in replacement of the eponymous one, which had been destroyed to build the new walls. The design was by Domenico Giunti. The small bell tower was added in 1607, while the façade was finished only in 1630, in late-Mannerist or early-Baroque style. The church is one of the few in the city which was not restored in 'neo-medieval' style during the 19th century.
It has a single nave with side chapels and barrel vault, a transept and a deep presbytery. Artworks include works by Gaudenzio Ferrari, Antonio Campi, Morazzone, Simone Peterzano, Ottavio Semino, Camillo Procaccini and Giulio Cesare Procaccini. The triumphal arch has a frescoes with a solemn Incoronation of Mary by Stefano Maria Legnani.
In the transept is the tomb of Blessed Beatrice Casati, the wife and widow of Francino Rusca, the Earl of Locarno. She raised four children -- three sons and one daughter, the latter of whom placed this monument to their mother -- and was a devout member of the Franciscan tertiaries. She died in 1490.
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.