Description : The church differs from all of the other monuments, apart from the fact that, it is the largest medieval building in Athens, but also from the fact that it follows a different architectural type, the octagon. It is a variation of the cross-in-square church but in this case the dome is supported by eight pilasters peripherally. It is also named the Russian Church because it is the parish church of the Orthodox Russian community in Athens. Its architectural structure forms an octahedral dome with a low tympanum. The dome covers the whole center of the church and it is supported by four square columns. The layout is constructed in such a way that unifies the internal space and at the same time adding a sense of grandeur. This architectural type of the church follows faithfully the original structure of Osios Loukas monastery in the town Distomo in Biotia, which is dated around the first half of the tenth century. It is of Middle Byzantine architecture and has been listed on UNESCO's World Heritage sides, along with the monasteries of Nea Moni and Dafnion. Rich ornamentations flank the North side of the Agia Triada church with kufic motifs and dentil bands. Three apses exists on the East side of the church, while on the West there are three square portals decorated with marble frames and brick arches. The Holy Sanctury is segregated from the main nave with a distinctively high iconostasis according to the Russian order and replaces the low Byzantine templon screen. On the left-hand of the church, lies the chapel of Saint Nikodimos, and on the right hand side lies the chapel of Saint Nikolaos. In 1847 the church was bought by the Russian government which undertook also the huge renovating expenses, so as to be used as a parish church of the Russian Orthodox community in Athens and was dedicated to the Holy Trinity (Agia Triada). The Western iconographic style of the church murals is a work of Ludvig Thiersch (1847), which covered the still extant Byzantine frescoes. The impressive bell-tower standing today was added when the church was renovated. The church opening of the reconstructed church were done in 1855 and from then the church's name establish as Holy Trinity (Agia Triada)
