More linguistically-interesting things I saw in Paris.
the Panthéon. This is one of the rare monuments that actively encourages visitors to touch and interact with it: a bust, electronically illuminated Braille inscriptions, and audio recordings.
Pompidou Center. Here the Braille inscription and a textured pattern allow the visitor to appreciate a work of visual art.
Inside the Louvre Museum there's a series of signs that lay down "les règles de l'art" [the rules of art], i.e. what you're forbidden to do inside (e.g. no touching artworks, no flash photography etc.). I like the humorous and non-verbal aspect of these signs:
And, finally, a trilingual notice in the Palace of Versailles: