A nationwide ceasefire between Syrian government forces and rebel groups has come into effect.
The truce, brokered by Russia and Turkey, which will act as guarantors, began at midnight (22:00 GMT).
The deal includes many rebel groups but not jihadists such as the so-called Islamic State, or the Kurdish YPG.
The ceasefire appeared to be holding in most areas early on Wednesday, If it continues, peace talks are due to be held in Kazakhstan within a month.
The Syrian Observatory for Human Rights, a UK-based group monitoring the conflict, said most of the country was calm in the first few hours of the truce. However it reported a clash between rebels and government forces in Hama province.
At least 300,000 people are believed to have been killed in fighting that followed the uprising against President Bashar al-Assad in March 2011.
A further four million have sought refuge in neighbouring states or Europe.