The Pothole of Cyrene
The Big Hole of Cyrene: the place is located a few kilometres east of Cyrene, in a private farm, and therefore access to it requires permission from the owner. It is locally known as Haw Hajyre; Hawa Al-H'ajer; or Hawa Ihjeyry: هوا احجري, which could mean a hole (or depression) in the rocks, or more like "a drop in the ground". The pothole was said to be 220 meters deep.
According to Mr. Tomasz Paul, his father Mr. Krzysztof Paul had reached the bottom of the hole on the 4th of November 1983; and that his father had left a letter in a jar at the bottom of the hole, with his name, address and a request for a letter if someone manages to do it again. He had also provided us with the following images of an article published in Jaskinie ('Cave') Magazine (2006), which gives more information about the successful descent:
According to (www.sktj.pl/epimenides/jaskinie/jask43.htm):
The Big Hole of Cyrene is in effect a vertical cave or a pothole of the type known as Karst Geology. The sides of the hole show that they were previously subjected to water or wind scouring. Examples of similar holes include the Golondrinas in Mexico (350 meters deep), and the Gaping Ghyll in England (50 meters deep). Karst regions are distinctive landscape features, many of which have flutes, tunnels, and grikes (generally called karren or lapiez), sinkholes or cenotes (closed basins), dolines, vertical shafts, disappearing streams, and karst towers. Many of these features were found to hide complex underground drainage systems (such as karst aquifers) and extensive caves and cavern systems beneath the surface. In fact the karst topography itself is characterized by subterranean limestone caverns carved by groundwater. The name "karst", originally from the Indo-European karra ('stone'), was derived from Jovan Cvijić's study "Das Karstphänomen (1893)", which established that rock dissolution was the key process responsible for creating most of the dolines.
A view of the pothole in relation to the nearby landscape, to indicate the size of the hole.