The valley or wadi of Nahal Mishmar begins in the Hebron hills, running east towards the Dead Sea. Its western part is shallow, at an altitude of approximately 270 m above sea level, and it proceeds to fall more than 300 meters into the Jordan Rift Valley before emptying into the Dead Sea, over 12 kilometres (7.5 mi). Nahal Mishmar runs north of the Tze'elim Stream, between Ein Gedi and Masada. Access is from Highway 90.
In 1961, Israeli archaeologist Pessah Bar-Adon discovered a hoard of Chalcolithic artifacts in a cave on the northern side of Nahal Mishmar, known since as the Cave of the Treasure. The hoard consisted of 442 decorated objects made of copper and bronze (429 of them), ivory and stone, including 240 mace heads, about 100 scepters, 5 crowns, powder horns, tools and weapons. Archaeologist David Ussishkin has suggested the hoard was the cultic furniture of the abandoned Chalcolithic Temple of Ein Gedi. Prominent finds from the hoard are currently on display in the archaeology wing of the Israel Museum in Jerusalem.
It is probable that the copper used for producing the objects was mined in Wadi Feynan.
Many of these copper objects were made using the lost-wax process, one of the earliest known uses of this complex technique.