Church of the Pantanassa

The Church of the Pantanassa (Greek: Εκκλησία της Παντανάσσης) or of the Dormition of the Theotokos (Ιερός Ναός Κοιμήσεως της Θεοτόκου) is the 10th-century katholikon of a now-vanished monastery in Monastiraki Square, between Athinas and Mitropoleos streets, facing the Monastiraki station, in central Athens, Greece. The church was known as the Great Monastery, and then later as monastiraki ("little monastery"), which eventually became the name of the whole area.

source https://en.wikipedia.org/wiki/Church_of_the_Pantanassa,_Athens