Ritual Bath

View of one 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 lead pipe (still in tact) that connects the basins, and on the far wall of the far basin note the lead pipe leading into it.

See Netzer, Ehud, and Rachel Laureys–Chachy. The Architecture of Herod, the Great Builder. Grand Rapids: Baker Academic, 2008, pp. 42–80.