ISTANBUL >> Rescue crews in Istanbul and Athens on Tuesday cleared roads that had come to a standstill after a massive cold front and snowstorms hit much of Turkey and Greece, leaving countless people and vehicles in both cities stranded overnight in freezing conditions.

Highways and roads in and around Istanbul became clogged on Monday after the storm pounded the city of about 16 million people that straddles the European and Asian continents — accumulating more than 80 centimeters (31 inches) of snow in some areas.

Stranded motorists either spent the night in cars, abandoned their vehicles to walk home or crowded subways and other public transportation.

All highways and main roads were reopened by Tuesday afternoon, Transportation and Infrastructure Minister Adil Karaismailoglu announced on Twitter, while Istanbul Gov. Ali Yerlikaya said that restrictions placed on vehicles traveling into Istanbul was lifted.

Authorities also cleared a runway at Istanbul Airport on Tuesday, allowing limited flights to resume. Flights were suspended on Monday for safety reasons at the airport, where the roof of a cargo facility collapsed from the weight of the snow. Istanbul’s second airport, Sabiha Gokcen, was also operating limited services.

Hundreds of passengers stranded at Istanbul Airport shouted “we need (a) hotel” in protest at their ordeal, Cumhuriyet newspaper reported.

In Athens, rescue crews freed around 200-300 drivers who were trapped on a major highway that runs across Athens and connects the Greek capital with the city’s international airport.

Drivers there had similarly abandoned their cars and walked home. Others had trekked to a nearby train station, jumping over the barriers at the side of the road to reach the platform after spending the night in their cars. The train service had been suspended, but a train was there Tuesday morning to pick up those who had made it to the station from the highway.

The army was sent out overnight to deliver food and water to those trapped and to help free as many as possible.

The heavy snowfall had mostly stopped on Tuesday, but many streets in Athens remained blocked by trees whose branches snapped under the weight of the snow. Several neighborhoods in the Greek capital, particularly in the northern part of the city, remained without power.

Authorities had ordered all but essential public and private businesses shut on Tuesday, and have extended that for Wednesday as well in the wider Athens area and several other regions of Greece. Coronavirus vaccination appointments for Wednesday were also being rescheduled for later dates.

Istanbul’s Disaster Coordination Center, or AKOM, said an Icelandic low-pressure system is behind the cold front and precipitation affecting most of the country.

Rescue teams in the city worked overnight to clear snowy roads and highways, but abandoned vehicles hampered their operations.

Interior Minister Suleyman Soylu said the snowfall in and around Istanbul would continue until Thursday and urged people not to venture out in private cars unless necessary. He said many of the stranded vehicles weren’t fitted with snow tires.

“Nothing is moving. The snow ploughs can’t even reach us,” Ahmet Odabasi, 40, one of thousands of travelers who was stranded overnight on a highway west of Istanbul, told The Associated Press by telephone earlier.

Authorities in Greece had warned people to limit their movements to the essential only and to use snow chains on city streets, but many people had set out for work in the morning when the snowfall was much lighter and became trapped in their cars as the day wore on. Some of the problems were reportedly caused by trucks that slipped and jack-knifed across the road, blocking traffic.

The snowstorm, complete with thunder and lightning, hit the wider Athens area late in the morning Monday, dumping large amounts of snow on the city. It is the second year in a row that Greece has experienced a freak snowstorm. Last year, similar weather in February left tens of thousands of trees felled by the weight of the snow on city streets, parks and woodland around Athens.

Officials said the Greek prime minister contacted the highways administration and asked for each trapped driver to receive 2,000 euros ($2,265) in compensation, which the highway administration accepted.

“It was a very difficult night and we faced unprecedented conditions,” Civil Protection and Climate Change Minister Christos Stylianides said. “I want to again express an apology from the state for all the difficulties that the (stranded) drivers faced.”

The severe weather also brought rare snowfall to vacation resorts in Turkey’s southwest region, including Bodrum and Datca, with snow and slippery conditions blocking a highway linking the provinces of Mugla and Denizli. Antalya city center, on Turkey’s Mediterranean coast, saw its first snowfall in 29 years, the private NTV television reported.

On Monday, authorities in Istanbul had suspended intercity bus services and blocked travel to the city from Turkey’s northwestern Thrace region. Civil servants were given leave until Thursday, except for those employed in security, health and transportation sectors. Schools across Turkey were already closed for a winter break and universities decided to close until Jan. 31.

Imamoglu said the Istanbul municipality has provided shelter to around 1,500 homeless people. Teams have left some two tons of food for stray cats and dogs, Imamoglu said.

The mayor said he hoped the snow would fill dams and bring relief to the region, which has been suffering from a dry spell.

The Balkans was also gripped by freezing weather, with temperatures dropping way below freezing in Serbia, Montenegro, Bosnia and Croatia.

Montenegrin authorities said the lowest ever temperature was confirmed in the northern Kosanica village, plunging to minus 33.2 C (minus 27.7 F). Previously, the lowest recorded temperature was minus 32 C (minus 25.6 F), registered back in 1985 in the northern town of Rozaje.

In Croatia, authorities urged people to be careful, dress warmly, avoid physical strain and watch their step on icy streets and roads. In Bosnia, ice formed on a part of the Miljacka river after minus 15 C (5 F) was recorded in the capital, Sarajevo, on Tuesday morning.