Aleppo's western suburbs are home to a group of historical sites and villages which are commonly known as the Dead Cities. Around 700 abandoned settlements in the northwestern parts of Syria before the 5th century, contain remains of Christian Byzantine architecture. Many hundreds of those settlements are in Mount Simeon (Jabal Semaan) and Jabal Halaqa regions at the western suburbs of Aleppo, within the range of Limestone Massif. Dead Cities were inscribed as a UNESCO World Heritage Site in 2011, under the name of Ancient Villages of Northern Syria.