I did Carmen :) I remember thinking how it looked like a sand castle, made of mud. Fragile, but pliable at the same time. On the inside I just remember looking up to what I believe were flowers on the ceiling, the pillars were shaped like tree trunks and branches reaching up.
It is massive, a lot to take in, so you have to leave for a while, eat some roasted chestnuts,drink a cup of sangria, then go back and experience seeing all over again.