Archaeological Site of Mystras

The site of Mystras includes a fortress, a palace, churches and monasteries, like this one in the postcard. 

Pantanassa Monastery in Mystras

This postcard arrived from Germany sent by Svenja

Mystras, the ‘wonder of the Morea’, lies in the southeast of the Peloponnese. The town developed down the hillside from the fortress built in 1249 by the prince of Achaia, William II of Villehardouin, at the top of a 620 m high hill overlooking Sparta. The Franks surrendered the castle to the Byzantines in 1262, it was the centre of Byzantine power in southern Greece (...)

Mystras, as the centre of Byzantine power, quickly attracted inhabitants and institutions; the bishopric was transferred there from Sparta, with its cathedral, the Metropolis or church of Hagios Demetrios, built after 1264. Many monasteries were founded there, including those of the Brontochion and the monastery of Christos Zoodotes (Christ the Giver of Life). Under the Despots, Mystras reached its zenith with the building of churches, outstanding examples of Late Byzantine church architecture, such as Hagioi Theodoroi (1290-1295), the Hodegetria (c. 1310), the Hagia Sophia (1350-1365), the Peribleptos (3rd quarter of the 14th century), the Evangelistria (late 14th – early 15th century) and the Pantanassa (c. 1430).  - in: https://whc.unesco.org/en/list/511/