The fortress, believed to have been constructed around 120 BCE by its namesake, John Hyrcanus, was one of seven ordered built by King Herod to protect the eastern border of the Judean Kingdom from the Edomites and other enemies.
During the Byzantine period, a monastery was built on the ruins by monks, whose bodies were buried in the cave, which was only recently identified and has not been excavated.
Shattered skeletons, shovels, cigarette butts, coffee cups, and a net used to filter the dirt were found in the desecrated cave by members of Preserving the Eternal, a local consortium founded one year ago by volunteers who seek to protect such sites.
http://www.jpost.com/Israel-News/Tomb-raiders-vandalize-mysterious-Judean-Desert-skull-cave-505009