Airports in Britain, Germany, France, Spain, the Netherlands and Denmark reported cancelations or delays to flights.
London's Gatwick airport reopened late afternoon after 150 employees using dozens of plows worked to clear the runway of 10 centimeters (four inches) of snow, though officials warned flights would be limited and cancelations likely.
Heathrow Airport will remain shut until Sunday after snow and ice forced the closure of runways, according to a statement on its website.
"There are likely to be significant knock-on delays tomorrow (Sunday) and you should contact your airline before traveling to the airport," the statement said.
Conditions on British roads were treacherous, Automobile Association official Darron Burness said. "One of the biggest problems is that large amounts of snow are falling very quickly on to frozen surfaces, making driving hazardous," he said.
Hundreds of motorists were left stranded on a major road in northwestern England following a deluge, prompting police patrols to offer food and water to drivers.
Jeremy Clarkson, host of BBC motoring program "Top Gear" said he was among drivers forced to abandon their vehicles close to Oxford, west of London. "It was very bad out there," he said.
In Italy, the Autostrada of the Sun - the country's main north-south highway - was jammed with hundreds of vehicles, whose chilly occupants slept in their cars, vans or trucks. Though snow had mainly cleared or melted early Saturday, the highway was still closed in one direction, with traffic backed up for nearly 25 miles (40 kilometers).
The snowfall also forced high-speed trains to bypass Florence's central Santa Maria Novella station, stopping in suburban stations instead.
Paris was sprinkled with a light coat of snow overnight, as many people prepared to set off on their Christmas vacations. More snow was predicted Saturday, leading civil aviation authorities to cancel 15 percent of flights at Charles de Gaulle airport between 4 p.m. (1500 GMT, 10 a.m. EST) and 11 p.m. (2200 GMT, 5 p.m. EST).
Many flights were also canceled in northeastern France, where snow already blanketed the ground, and services were also canceled at the airports in the cities of Nantes and Rennes.
Significant numbers of domestic and European flights were canceled at Germany's Frankfurt airport as it dealt with the disruption. Germany's railway operator Deutsche Bahn said it was pressing into service all the trains it could - though some journeys were subject to delays. "Everything that can roll is rolling," spokesman Holger Auferkamp told the German news agency DAPD.
The icy weather also swept over large parts of Scandinavia, causing problems particularly in Denmark, where dozens of flights were canceled at the airport in Copenhagen. According to Danish news agency Ritzau, train traffic between Denmark and southern Sweden was also disrupted because of track problems, partly due to the snow, forcing passengers to instead take buses between the two countries.
In Sweden, where media reports suggest the country is experiencing the coldest winter weather this early on in the season since the mid-1800's, several road accidents were reported, with more than 20 in the Stockholm area alone.
Retailers said the poor weather would likely dent sales on what it traditionally the busiest shopping weekend before Christmas. London's Brent Cross indoor shopping mall closed its doors early Saturday afternoon.
Elsewhere, a snowman greeted tourists at London's Camden Market, while traders broke up ice and snow with shovels on the cobblestone paths. Two groups of tourists hurled snowballs at each other across the canal on the edge of the market.
Britain may experience its coldest December on record, weather service forecaster Mark Seltzer said.
"Temperatures will struggle to get over freezing and although the snow should ease off tonight, it will return to eastern areas on Sunday," he said.
Police in Leicester, central England, said the snowy weather had helped uncover a cannabis factory in the city. Officers raided the premises after spotting that snow had melted on the building's roof as a result of heat from industrial-strength lights used in the cultivation of the drug.
Horse racing meetings and dozens of soccer games in England and Scotland were called off as a result of the conditions, including a high profile match scheduled for Sunday in London between Chelsea and Manchester United.
Angela Doland in Paris, Geir Moulson in Berlin, Frances D'Emilio in Rome, Frank Griffiths in London and Louise Nordstrom in Stockholm contributed to this report.