Santa Maria Maggiore church is an example of First Romanesque art. It includes the oldest cross vaults in Italy.
The oldest document mentioning the basilica is a privilege by pope Paschal II, dated 22 August 1107. Archaeological studies showed that at least two churches existed in the site before the current one, the earliest one being perhaps contemporary to the annexed baptistery of San Giovanni ad Fontes (c. 5th-7th centuries). The basilica has a nave and two aisles with a lower transept. The façade was originally embedded in the city's walls, but later the first three bays were abandoned and a new façade was obtained by closing one of the internal arches with a new wall.
The nave is characterized by arches which, at the sides, have double mullioned windows at the sides. The pillars which do not support the arches are prolonged by blind columns up to the clerestory. The longitudinal arches (those separating the nave from the aisles) are supported by semicolumns which form the pillars. The aisles are a 14th-century reconstruction of the original ones. In 1944 a crypt, perhaps unfinished, was discovered.
Adejacent to the basilica is the nearly coeval Baptistery of San Giovanni ad Fontes.
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.