The Church of Agioi Theodoroi is one of the oldest and largest chapel in Mystras. It is located in Kato Hora, the lowest part of Mystras Old Town. The church was constructed between 1290-1295 by the monks Daniel and Pahomios. Originally, it was the katholikon of a monastery and then it became a cemetery church.
The architecture of the church is different than the usual Byzantine architecture and ressembles to the Monastery of Osios Loukas in Distomo Boetia, but in a more developed form. The architecture gradually points to the top and the dome is pretty impressive. The interior of the church distinguishes for the impressive frescoes that date from the 13th century, such as the portraits of the Emperor Manuel Paleologos. In this church, there is also the tomb of the Despot of Peloponnese Theodore I.
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.