It's home to some of the most ancient Christian monasteries, and its natural caves or 'hermitages,' were used as shelters and burial grounds going back more than 10,000 years.
VOA: standard.2010.08.05
The uniquely Islamic religious character witnessed in the 'city of dead', is a consequence of the grouping of princes' and rulers' mausoleums close to the tombs and khanqahs (hermitages) of saints revered by them.