A Siberian cold front has dumped heavy snow on Rome for the first time in six years, paralysing a city used to mild winters and giving priests the opportunity to pelt each other with snowballs.
Snowfall started about 2:00am (local time) and lasted for nearly 10 hours, covering Rome in nearly 10 centimetres of snow.
Schools and kindergartens remained shut, while train services and public transportation were crippled. Fallen tree branches in some parts also blocked roads causing traffic congestion.
The city's parks, which usually stay green, instead turned white, prompting locals, seminarians and tourists to make the most of the winter wonderland and launch snowball war.
The World Meteorological Organisation says the chill in Europe is caused by a "sudden stratospheric warming" above the North Pole that led to a split in the polar vortex, a cold area of air above the Arctic that spilled cold south.
The Arctic storm dubbed the "Beast from the East" saw temperatures across much of Europe fall on Monday to their lowest level this winter.
"Many of us didn't go to work and children aren't going to school today either," said Mariangela Barbanente, a local resident.
"The piazzas look lovely after snow. Rome received its last snow six years ago in 2012.
"Back then my child was not even born, and now he is two and a half years old."
Due to continued freezing weather conditions, the city's schools will remain closed even on Tuesday while workers will finish their clean-up work.
The Siberian weather system, which is slowly moving across the continent, is causing several places to feel as cold as the Arctic Circle.
Elsewhere in Europe, the storm set dangerously low temperatures, with some places in Lithuania dropping to a low of -24C.
The weather was blamed for at least three deaths on the weekend.
Similar sudden drops have occurred over North America in recent years and climate researchers say they could become more common as global warming further saps strength from the air currents around the pole.
Another round of snow is expected in the country's north next week, according to the local weather bureau.