Hyrcania was an ancient fortress in the Judean Desert. The site was rebuilt during the Byzantine period as a monastery called Kastellion.
The site is located on an isolated hill about 200 m above the Hyrcania valley, on its western edge. It is about 5 km west of Qumran, and 16 km east of Jerusalem. The site has not yet been thoroughly excavated. Current knowledge about the ruins of the site is based on a limited number of test pits.
Coordinates 31°43'8.049" N 35°21'55.943" E