The cathedral is set on a flat lowland amidst the old town of
Mtskheta, as its most significant structure, visible from nearly every spot. The base of the three-storey
basilica, believed to have been built by
Vakhtang Gorgasali after
St. Nino's original church, was found by archaeologists during the 1970–71 restoration. Its remnants can be seen in the western and southeastern parts, as well as under the pillars beneath the floor. The remains of an even older wooden church were discovered in the southern arm of the cross. The architecture of the present Svetitskhoveli Cathedral, which dates from around 1020, is based on the
cross-dome style of church architecture, which emerged in Georgia in the early Middle Ages and became the principal style after the political unification of Georgia by
Bagrat III (978–1014). A characteristic of this style is that the dome is supported across all four sides of the church. There was originally a more harmonious three-step silhouette, with porticoes on the south, west, and north. The northern and southern porticoes were demolished in the 1830s. The current entrance to the cathedral is from the west. The church's structure is intended to ensure good acoustics. Large windows on the dome and walls provide ample light. The church's plan is a cross, with shorter transverse arms and longer longitudinal arms. The east end contains an
apse. The dome of Svetitskhoveli was reconstructed several times over the centuries to maintain the church in good condition. The current dome is from the 15th century, with its upper part reconstructed in the 17th century, when it lost its original height and was reduced in size. The primary stone used for the cathedral is sandy yellow with trimmings, while a red stone is used around the apse window. The green stone used in the drum of the cupola dates from the 17th century. The church facades are richly decorated. The curved blind arcading is preserved from the 11th century. The arches genuinely ascend or descend according to the height of the corresponding section of the facade, creating an impression of constant movement. Two high and deep niches on the eastern facade stand in clear contrast with the surrounding illuminated walls. Each window is framed by an ornamental stripe and stylized
peacock tail-like decorations. Similar decorations are appear in the upper parts of the eastern niches. A writing above the windows of the eastern facade states that the church was built by katolikos
Melchisedek. Above it, two
low-reliefs — an eagle with open wings and a lion below it — are positioned to the south of three more recent accessory windows beneath the roof. A large window occupies most of the western top side of the church. Its decoration depicts the
Ascension of Jesus, with Christ seated on the throne and two angels on both sides. This triangular decoration fits harmoniously with the triangle of the
cornice and the arch below it. The original sculpture on the wall has not survived but has been restored several times, most recently in the 19th century.
The architect Arsukidze A legend surrounds a relief sculpture on the external northern wall. It depicts a right arm and hand holding an L-square — the stonemason’s symbol — with an inscription reading: An inscription on the east façade further attests that Arsukidze did not live to see his masterpiece finished (in 1029):
Konstantine Gamsakhurdia's novel
The Hand of the Great Master recounts the legend, for which there is no documentary evidence, that a priest who had also been Arsukidze's patron and teacher was so jealous of Arsukidze's success that he used his influence with the king to have the architect's right hand cut off. According to the novel, King George was also jealous of his lover, the beautiful Shorena.
Icons and frescoes The cathedral's interior walls were once completely adorned with medieval frescoes, but many of them have not survived. In the 1830s, when
Emperor Nicholas I was scheduled to visit Mtskheta, Russian authorities demolished the galleries and whitewashed timeless frescoes to give the cathedral a "tidier appearance"; in the end, the Czar never visited. Today, after careful restoration, some frescoes survive, including a 13th-century depiction of the "Beast of the Apocalypse" and figures of the
Zodiac. The walls are decorated with many Christian Orthodox
icons, most of which are not original (the originals are preserved in the national museums of Georgia). The church's stonework also features carved grapes (as in many churches of Georgia), reflecting the country's ancient wine-making traditions. The large figure of Jesus at the altar was painted by a Russian artist in the 19th century. The majority of the icons date to the 20th century, with some being copies of older icons and frescoes from other churches across Georgia. Two bulls' heads on the east façade, remnants of the 5th-century church, attest to the folk influence on Christian iconography during that early period.
Baptismal font On the right side of the entrance is a stone baptismal font dating from the 4th century. It is thought to have been used for the baptism of King Mirian and Queen Nana. Immediately behind the font is a reproduction of the relief of Arsukidze's right hand and bevel from the north facade.
Symbolic copy of the Chapel of Holy Sepulchre of the
Church of the Holy Sepulchre On the south side, a small stone church is built into the cathedral. This is a symbolic copy of the Chapel of
Holy Sepulchre in
Jerusalem. Constructed between the late 13th and early 14th centuries, it was erected to mark Svetitskhoveli as the second most sacred place in the world (after the church in Jerusalem), owing to Christ's robe. In front of this stone chapel, the most westerly structure aligned with the columns between the aisle and the nave marks Sidonia's grave. Remains of the original life-giving pillar are also here. The chapel was built in the 17th century. Scenes depicting the lives of King Mirian and Queen Nana, and portraits of the first Christian
Byzantine Emperor,
Constantine I, and his mother
Helena, were painted by G. Gulzhavarashvili at that time. Traces of the foundations of the 4th-century church have been found here.
Throne of Catholicos-Patriarch The second structure aligned with the columns of the southern aisle was also built in the 17th century as the throne of Catholicos Diasamidze. It no longer serves this function, as current tradition requires the Georgian patriarch's throne to be at the centre of the church. ==Burials in the cathedral==