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View looking down into a plastered ritual bath found on the acropolis of Machaerus. Note the three stairs on the left that lead down in the bath and the plaster still coating the stonewalls.
Jews used, and still use, this type of bath—a miqveh—for ritual purification purposes. Note that the fortress was first built by the Jewish Hasmonean ruler Alexander Jannaeus, and that it was subsequently controlled by a series of Jewish rulers before the Jewish Zealots surrendered the acropolis to the Romans in A.D. 72. Thus a miqveh is not unexpected here at Machaerus.
This image courtesy of Mark Connally.