The most important building of the great necropolis is the Treasury, most likely the mid-1C AD tomb of King Aretas IV, and today the symbol of Petra. Like the other tombs, it is entirely hewn from sandstone, with a façade measuring 40m in height and 28m across, showing strong Hellenistic influence. According to legend, the surmounting stone urn hid a treasury (khazneh in Arabic), hence the building's name.