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 Kalozha church of Saints Boris and Gleb is the oldest extant structure in Hrodna. It is the only surviving monument of ancient Black Ruthenian architecture, distinguished from other Orthodox churches by prolific use of polychrome faceted stones of blue, green or red tint which could be arranged to form crosses or other figures on the wall.
The church is a cross-domed building supported by six circular pillars. The outside is articulated with projecting pilasters, which have rounded corners, as does the building itself. The ante-nave contains the choir loft, accessed by a narrow gradatory in the western wall. Two other stairs were discovered in the walls of the side apses; their purpose is not clear. The floor is lined with ceramic tiles forming decorative patterns. The interior was lined with innumerable built-in pitchers, which usually serve in Eastern Orthodox churches as resonators but in this case were scored to produce decorative effects. For this reason, the central nave has never been painted.
The church was built before 1183 and survived intact, depicted in the 1840s by Michał Kulesza, until 1853, when the south wall collapsed, due to its perilous location on the high bank of the Neman. During restoration works, some fragments of 12th-century frescoes were discovered in the apses. Remains of four other churches in the same style, decorated with pitchers and coloured stones instead of frescoes, were discovered in Hrodna and Vaŭkavysk. They all date back to the turn of the 13th century, as do remains of the first stone palace in the Old Hrodna Castle.
In 2004, the church was included in the Tentative List of UNESCO"s World Heritage Sites.