The first arrivals in mid-1915 were accommodated in Aleppo, but from mid-November the convoys were denied access to the city and redirected along the Baghdad Railway or the Euphrates towards Mosul. The first transit camp was established at Sibil, east of Aleppo; one convoy would arrive each day while another would depart for Meskene or Deir ez-Zor. There were 25 concentration camps in Syria and Upper Mesopotamia. In late 1915, the camps around Aleppo were liquidated and the survivors were forced to march to Ras al-Ayn; the camps around Ras al-Ayn were closed in early 1916 and the survivors sent to Deir ez-Zor.