Following a medieval Georgian tradition of naming churches after particular places in the Holy Land, the Sioni Cathedral bears the name of Mount Zion at Jerusalem. It is commonly known as the 'Tbilisi Sioni' to distinguish it from several other churches across Georgia bearing the name Sioni.
It was initially built in the 6th and 7th centuries. Since then, it has been destroyed by foreign invaders and reconstructed several times. The current church is based on a 13th-century version with some changes from the 17th to 19th centuries. The Sioni Cathedral was the main Georgian Orthodox Cathedral and the seat of Catholicos-Patriarch of All Georgia until the Holy Trinity Cathedral was consecrated in 2004.
The cathedral's interior took on a different look between 1850 and 1860, when the Russian artist and general Knyaz Grigory Gagarin (1810–1893) composed an interesting series of the murals, though a number of medieval frescoes were lost in the process.
The Sioni Cathedral is a typical example of medieval Georgian church architecture of an inscribed cross design with projecting polygonal apses in the east façade. The yellow tuff from which the cathedral was built comes from Bolnisi, a town southwest of Tbilisi. The facades are simple, with few decorations, although there are bas-relief carvings of a cross and a chained lion on the western side and an angel and saints on the north. All sixteen windows have carved ornamental frames.
North of the cathedral, within the courtyard, is a freestanding three-story bell tower dating from the 1425 reconstruction by King Alexander I. Largely destroyed by the Persians in 1795, it was restored to its present condition in 1939. Across the street stands another three-story bell tower; one of the earliest example of Russian Neoclassical architecture in the region. Complete in 1812, the bell tower was commissioned under Pavel Tsitsianov using money awarded in recognition of his conquest of Ganja for the Russian Empire.
References:Visby Cathedral (also known as St. Mary’s Church) is the only survived medieval church in Visby. It was originally built for German merchants and inaugurated in 1225. Around the year 1350 the church was enlarged and converted into a basilica. The two-storey magazine was also added then above the nave as a warehouse for merchants.
Following the Reformation, the church was transformed into a parish church for the town of Visby. All other churches were abandoned. Shortly after the Reformation, in 1572, Gotland was made into its own Diocese, and the church designated its cathedral.
There is not much left of the original interior. The font is made of local red marble in the 13th century. The pulpit was made in Lübeck in 1684. There are 400 graves under the church floor.