Another of the ritual baths (miqveh) excavated at Jericho. It consists of two pools, the far one to collect the water and the near one, with the staircase leading into it, for immersion—ritual cleansing. In the wall separating the two basins, note the small channel that connects the two basins and around the sides of the basins the channels that lead into them.
See Netzer, Ehud, and Rachel Laureys–Chachy. The Architecture of Herod, the Great Builder. Grand Rapids: Baker Academic, 2008, pp. 42–80.