Residing over Plaza del Mercado Grande, San Pedro projection is similar to that of the Basilica of San Vicente. The monarchs swore their respect for the charters of Castile in the atrium of the church, which underlines its importance during the period in which the town achieved its greatest relevance in the world of politics.
San Pedro has a Latin-cross layout with a central nave that is larger than the side naves. Its construction began in the second quarter of the 12th century and was completed in the 13th century after a period in which the work was stopped. The architecture and decoration shows an evolution of particular interest as a result of the delays in the construction work.
It has a triple upper end with an apse on each nave and a magnificent collection of sculptures showing plant, animal and geometric motifs and scenes from the Bible. The ceilings were covered with barrel and groined vaults in the 13th century. Over time, the arches became forerunners to those used in the Gothic period. Finally, a tower was built on the place where the central nave intersects with the transept.
The main front has two bodies: the upper body is dominated by a large rose window and the lower body has a porch in which the size of the entrance is magnified by six plain archivolts. The southern porch is similar but smaller in size. The northern entrance is more ornamental and moulded with five archivolts, two of which are decorated with typical Ávila-style rosettes.The interior stands out thanks to the panels distributed around the walls of the nave, the Renaissance-style altars and the altarpiece in the main chapel, together with its grilles.It was designated a National Monument in 1914.
References:The Basilica of Santa Maria in Trastevere is one of the oldest churches of Rome. The basic floor plan and wall structure of the church date back to the 340s, and much of the structure to 1140-43. The first sanctuary was built in 221 and 227 by Pope Callixtus I and later completed by Pope Julius I.
The inscription on the episcopal throne states that this is the first church in Rome dedicated to Mary, mother of Jesus, although some claim that privilege belongs to the Basilica di Santa Maria Maggiore. A Christian house-church was founded here about 220 by Pope Saint Callixtus I (217-222) on the site of the Taberna meritoria, a refuge for retired soldiers. The area was made available for Christian use by Emperor Alexander Severus when he settled a dispute between the Christians and tavern-keepers.
The church underwent two restorations in the fifth and eighth centuries and in 1140-43 it was re-erected on its old foundations under Pope Innocent II.