Well of the medieval ritual Jewish bath (mikweh) in <a href="//commons.wikimedia.org/wiki/Syracuse" class="mw-redirect" title="Syracuse">Syracuse</a> (Italy). Entirely built underground, it was hidden when the Jews were expelled from all Spanish dominions (1492). Long since forgotten, therefore preserved intact, it was recently restored and opened for visits. Picture by <a href="//commons.wikimedia.org/wiki/User:G.dallorto" title="User:G.dallorto">Giovanni Dall'Orto</a>, May 22 2008.
<a href="//commons.wikimedia.org/wiki/User:G.dallorto" title="User:G.dallorto">G.dallorto</a>
Attribution
<span class="int-own-work" lang="en">Own work</span>