"UNITAR-UNOSAT [UN Operational Satellite Applications Programme] found a total of 290 locations inside these 18 [cultural heritage areas] to have been directly affected during the last three years," the UN agency said in the paper.
The report specified that in the 18 large cultural heritage areas, 24 locations were completely destroyed and 104 severely damaged.
The damaged locations included UNESCO World Heritage properties such over 7,000 year-old buildings in Aleppo, the report stated. Another site in danger is the Crac des Chevaliers, one of the most famous medieval castles in the world. Sites and antiquities in the northern city of Raqqa are also at risk.
Syria's civil war started as anti-government protests in the wake of the Arab Spring in 2011. The government forces are currently fighting a number of militias, including the Islamic State (IS) extremist group. The extremists have seized vast areas across the country, and proclaimed an Islamic caliphate on the territories under its control. Raqqa is one of the heritage-rich cities de-facto controlled by IS.