An estimated two million Russians plunged into icy waters on Monday night and Tuesday to mark the Christian holiday of the Epiphany, when Orthodox believers take part in an outdoor purification ritual.
People throughout the country stripped down to their swimsuits and took dips in cross-shaped holes cut into frozen rivers, lakes and ponds, a ritual that commemorates the baptism of Jesus by John the Baptist.
Some 90,000 people took part in the celebrations in Moscow undeterred by temperatures that dropped to around minus 8 degrees centigrade (18 degrees Fahrenheit) on Tuesday, authorities said.
Mobile pools filled with icy water were set up on the central Revolution Square near the Kremlin to accommodate city dwellers.
"While in the past there were cases when drunk people would flop into the water, now people understand that this is not some kind of game, that this is a sacred rite that requires spiritual preparation," emergency situations minister Vladimir Puchkov said Tuesday in a statement.
This extreme Orthodox ritual takes place every year from midnight to midnight between January 18 and January 19. Russia's Interior Ministry estimated some two million people had taken part as of Tuesday morning.
Bathers believe the annual ice plunge will purify them and the cold water will strengthen their bodies since it has been blessed by priests.
"We believe that this water is truly holy," 48-year-old businessman Andrei told AFP after his freezing dip in a Moscow pond.
"A few drops of this water purifies us and dispels evil thoughts."
Yelena, a 51-year-old nanny, also praised the ceremony's purifying benefits after taking a dip.
"I feel incredibly light," she said. "I feel so good."
Believers in the barren Siberian region of Sakha braved minus 40 degrees Celsius temperatures to take part in the ritual, the authorities said.
The emergency situations ministry said that 35,000 workers had been assigned to monitor the nation-wide winter ritual. No incidents were reported during this year's celebrations.