Istanbul woke up to a snow-covered city on Wednesday with some regions having up to 60 centimeters of snow.Heavy snowfall in Istanbul has significantly affected the largest city of Turkey since Tuesday as thousands of people have been stranded on the roads, while others were stuck in over-crowded public transportation.It was reported that almost 850 traffic accidents have occurred since Tuesday as most vehicles are not equipped with winter tires or chains to tackle the harsh weather conditions.Roads were covered with ice as the Metropolitan Municipality of Istanbul worked overnight to clean the main roads, bridges, and viaducts with over 4,800 staff and 1,028 vehicles.Over 15,000 tons of salt and 320 tons of antifreeze solution were used to prevent road accidents.No accidents have been reported on the main roads, the State Road D.100 and Trans-European Motorway said on Wednesday morning.Schools were closed on Wednesday due to heavy snowfall and extreme weather conditions according to the Istanbul Governorate.Şehir Hatları (City Lines), the operator of Istanbul's intercity ferries have cancelled some lines due to blizzard.Air travel was also negatively affected as hundreds of domestic and international flights were cancelled in Turkey's major aviation hub.