Over 700 abandoned settlements bear the collective name The Dead Cities or Forgotten Cities of Syria, located in northwest Syria between Aleppo and Idlib.
Most villages which date from the 1st to 7th centuries, became abandoned between the 8th and 10th centuries.The name might perhaps be considered ironic, bearing in mind what is happening in the country’s modern cities at the moment.
Many of these old cities shelter refugees. Other places like al-Bara have been bombed in to the ground and its inhabitants have fled to Serjilla. The total degree of devastation is not known yet. Access to this archaeological site is restricted due to the ongoing clashes with terrorists in this area. The videos below are from 2009.
Very detailed information about villages and buildings including photos is available here: http://www.syriaphotoguide.com/home/tag/dead-cities/
UNESCO World Heritage: http://whc.unesco.org/en/list/1348