The partial picture on the right of the ticket, must be the normal setting of the interior...
... but on this afternoon, a crew was setting up for a special party or celebration. Pretty much the whole time I was down here, "Hotel California" by the Eagles, was playing over the sound system, making this visit somewhat surreal.
A demo setup (behind plexiglass) off to the side. This 'cistern' seems to serve regular duty as a party spot.