Hijar (sing. hijra ) refers to two Arabian practices of demarcating and protecting space. The name of the practices is linked to the prophet Muḥammad's hijra (emigration) from Mecca to Medina in the year 1/622. In Yemen, hijar are protected enclaves in tribal territories. It has been suggested by Puin, Serjeant, and others that the practice may be of pre-Islamic origin and connected with the Ancient South Arabian term hgr (usually vocalised hagar ), which seems, in extant inscriptions, to denote administratively important towns. Madelung, however, has argued convincingly