I saw the Pantheon in Rome, which is nothing like this one. Inside you have several mural paintings (spot Jeanne d’Arc), and underneath tombs which are the resting place of the Curies and Victor Hugo. (Very cold but has a bathroom, not unimportant for ladies travelling :) ). The best part was the pendulum. I’ve seen one in Magdeburg before, and it is fascinating to watch. The theory is that the pendulum is actually still, while the world, including us, is moving around it. (There’s a little movie station in a corner which explains this.)