Throughout Petra you you will see several freestanding cube-shaped monuments, which are known as djinn blocks. 'Djinn' is the name for a type of spirit that features in Arab folklore; the name was adopted for these blocks as Petra's Bedouin occupants believed these monuments 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. In Bab el-Siq you can see three djinn blocks, and there are a total of 25 in Petra. The line drawings here are of djinn blocks as recorded by archaeologists in 1904. The first archeologists to complete an inventory of tombs in Petra assigned a number to each, and these are still used today. If you look around the djinn you will see a number of tombs and caves. Some of these tombs would have been for the poorer classes and are the earliest tombs carved in Petra (end of 2nd 10 beginning of 1st century B.C.)