Watch out after dark, at least if you are in Paris. Apparently, it is illegal to publish photos of the Eiffel Tower taken after dark without permission. Given the prevalence of photo books and other similar products this restriction seems extreme, but it exists nonetheless.
Apparently, in 2003 SNTE, which manages the tower, changed the lighting and then copyrighted the resulting image. SNTE was able to do this because French courts have upheld copyright based on the specific lighting. I doubt this trick would hold up in the U.S., but then the Eiffel Tower isn’t in the U.S.
The photo used to illustrate this article was taken in Las Vegas, so I’m not violating any laws.