Dozens of Greek Orthodox Christians swam frantically to retrieve a wooden cross thrown into Istanbul’s Golden Horn on Monday as today marks the beginning of Orthodox Christmas celebrations.

The Greek community in Istanbul was celebrating Epiphany, one of the Orthodox Church’s most important feasts, commemorating Jesus’ baptism in the River Jordan, as for some believers Christmas falls in January, due to calendar differences.

Patriarch Bartholomew I, the Istanbul-based leader of many of the world’s Orthodox Christians, threw a wooden cross into the icy waters of the Golden Horn after an almost five-hour religious ceremony at the nearby Patriarchate.

Read more: Istanbul’s Greek community takes deep dive for cross