We could not believe that this site is not as famous as some of the others (like Notre Dame) in Paris. Unlike the Pantheon in Rome, this building has more rooms and is much bigger. It feels more like St. Peter's Basilica (and there's a sign saying the Basilica was the inspiration).
The building itself is huge. Just enormous. There are beautiful paintings on the walls, and there is an awesome pendulum clock (Foucault Pendulum) in the center of the building that uses the rotation of the earth to keep time (which since I am studying physics at a university found fascinating).
The catacombs below were great to see, too. Many famous French people are buried there, like Voltair and Rousseau and Victor Hugo.
Do note that one cannot climb to the top of the Pantheon until April (closed at least from Jan-Feb, not sure about months like Nov and Dec). A sign also said that one can only go up with a guided tour, so do keep that in mind if you wish to go up.
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