Secret masses took place at this Greek-Orthodox church during the Soviet era. Note the several icons of saints inside!
Batumi tourism website http://gobatumi.com/en/feelit/about-batumi/sightseeing?product=85
Address Parnavaz Mepe str. 24, Batumi 6006, Georgia
Coordinates 41°39'0.793" N 41°38'28.701" E