Ma'agar Bet Zayit, reservoir in Israel

Ma'agar Bet Zayit is a seasonal reservoir in the Jerusalem District, set in the wooded hills west of the city and fed mainly by winter rains. The banks are low and open, lined with trees, and a dirt path connects the parking area to the water's edge.

A dam was built across the Nachal Soreq stream in the 1950s to collect rainwater for the surrounding agricultural land. The project was part of the early water development efforts of the newly established state.

The name Bet Zayit means "House of Olives" in Hebrew, referring to the olive trees long grown in this part of the Jerusalem hills. After a flood turns the reservoir into the only lake in the Jerusalem hills, the site becomes a focus for outings and picnics, with heavy traffic of hikers, athletes and cyclists, especially on Saturdays; small boats have also been seen on the water.

The reservoir is not officially open for recreation, and the water is not hygienically suitable because the Sorek also drains Palestinian areas around Ramallah without a sewage treatment system. The muddy shores have been the site of drownings, and mosquito swarms spread disease from the murky water in early summer. A bike path runs along the eastern side from Kerem junction to Motza Tachtit junction as part of the Jerusalem Surroundings Trail, with heavy foot, sport and cycling traffic on Saturdays.

The shallow water near the banks is home to fairy shrimp, tiny crustaceans that swim upside down and only live in clean, temporary pools. Their eggs can lie dormant in the dry soil for years and hatch only when the water returns.