agia grigoriou orthodox monastery at mount athos, agion oros, holy mountain, halkidiki , greece.

agia grigoriou orthodox monastery mount athos agion oros holy mountain halkidiki greece osiou sea travel architecture religion chalkidiki st gregory building historic mediterranean faith cloister gregoriou tower water landscape trees hill plants cliff bushes monk moni friar travelphotography landscapephotography church god spirituality greek view antique vacation history destination great pray october fall