Hampoeil or Pigeon cave is huge and dreaded limestone cave, yet is not entirely discovered. This cave is one of the wonders of Sahand mountains region. Near to this cave there is discovery of 200 thousand years of Stone Age human inhabit.
Hampoeil cave is very interesting one for cavers with wells up to a depth of 48 meters. They have been 8 halls identified in this cave which some of them are gathering place for water.
There are some livings in this cave such as bat that you might see them during your visit.