For hundreds of passengers trapped at the main Paris and Brussels airports overnight because of the freezing weather however, the nightmare drew to a close: European flights were almost back to normal Saturday.
For the first time since 1981, swimmers arrived at the Serpentine in London's Hyde Park for the 100-yard (91-metre) open-air race to find the lake had frozen over.
It was the result of a cold snap that forecasters predict could make this the coldest December in Britain for more than 100 years.
In Castlederg, Northern Ireland, the temperature was minus 17.1 Celsius (1.22 Fahrenheit) on Christmas morning.
On England's south coast, members of the Brighton Swimming Club took their annual Christmas dip in the Channel, where the temperature was a refreshing 3.3 degrees Celsius (38 degrees Fahrenheit).
On the Danish island of Bornholm even a tracked military vehicle failed to get through the snow to take a midwife to the village of Tejn -- so a colleague took to her skis instead.
Rene Wang Hansen said the midwife covered six or seven kilometres (four or five miles) to reach his daughter Gitte, who later was finally able to board an army personnel carrier to get to hospital for the birth of her son.
The Baltic island of some 43,000 people has been snowbound since Thursday with police advising everyone to stay at home. Hundreds of tourists and other visitors have been put up in a gymnasium and a military barracks.
In Germany, another Baltic island, Ruegen, was also snowbound and no trains were running, but rail operator Deutsche Bahn said conditions were improving elsewhere and there were no major problems.
In the northwestern state of North Rhine-Westphalia police warned pedestrians to be on their guard after a woman was killed Friday by a falling branch in the forest of Gelsenkirchen.
In Moscow, icy rainfall onto frozen streets turned the Russian capital into a giant skating rink, and authorities warned residents to stay indoors while they de-iced the roads and pavements.
Traffic is traditionally heavy in the run up to the new year and the Russian Orthodox Christmas, on January 7.
But local government spokesman Igor Pergamenshik warned: "Weather conditions are very difficult in the capital.
"When it (the rain) falls onto the ground, it turns into a layer of ice because of the negative temperatures."
Airlines took advantage of fewer Christmas Day flights to clear runways and the backlog of passengers, some of whom had waited for days to leave.
About 200 travellers woke up on Christmas morning at Paris's Charles de Gaulle airport after authorities had laid on what entertainment they could on Christmas Eve.
Departure screens showed nearly all flights due to leave on time, as staff folded away the camp beds that had been provided along with food, Christmas toys, a Santa Claus and a Catholic mass for the faithful.
"The children have presents, we have things to eat and drink," said Beatrice Clavel, stranded with her husband Didier and their two children.
"All that's missing is a good shower."
The problems at the airport were compounded by a strike by workers at France's main anti-freeze factory, but conditions improved when supplies arrived from abroad.
Transport Minister Nathalie Kosciusko-Morizet announced an inquiry into the airport's handling of its glycol stocks and said officials had to learn from experience, particularly with regard to providing information for passengers.
It was a similar story at Brussels' where some passengers had to sleep over into Christmas morning. On Saturday however, the situation was returning to normal.
"We’ve cleaned enough snow to be able to return to normal winter operations," said a statement on its website.
Virtually no public transport ran in Britain as usual on Christmas Day, not even Eurostars to and from the continent, but trains in France were back to normal, though high-speed services were still delayed by speed restrictions.
In contrast to the chilly conditions across Europe, Bulgaria experienced record highs of up to 20 degrees Celsius in some central parts, way above the seasonal average which is below zero.