The freestanding cube-shaped monuments you see here (and which are spread all over the area) are called Djinn-blocks, djinn being the name of a kind of spirit in Arab folklore. Bedouin occupants believed these cubes were the dwellings of djinn, which were thought to inhabit the area. Today it is generally agreed that these monuments served as tombs and memorials to the dead. There are a total of 25 in Petra, these three stand at the Bab el-Siq, the Gate to the Canyon. They were assigned numbers during the first inventory, they are number 7, 8 and 9 and date from 50 BC – 50 AD. They are surrounded by tombs for the poorer classes, which themselves are the earliest carved tombs in Petra (end 2nd Century BC, beginning 1st). Text from notice on site.