One of the biggest and most beautiful caves in Attica was discovered relatively recently. Afeyan Cave is located in the mountains Egaleo, in the western metropolitan area of ​​Haidari. In 2008, the entrance to a cave was discovered by local children and then it was examined and mapped by cavers.

Proceedings of the cave, formed as a result of cracks developing obliquely in a northwesterly direction. In the cave there are a variety of rock formations, including the curtains, stalactites and stalagmites, helictites, stalactite columns and other dripstones, many of which are distinguished by a special beauty and unusual, infrequent forms. The picture is completed by bizarre hanging tree roots. Factors such as temperature, seismicity of the area and the nature of the rocks, created interstices, which formed the natural cave decorations.

Numerous landslides hamper the research and mapping of the cave. Thus, currently  ¾ of cave is already mapped. Sloping terrain and landslides make the cave collapses unsuitable for tourist visits.