Security observations

We  the current political climate and recent attacks in Paris and Brussels, I wasn't sure what security measures would be in place.  At eachh of the sites we visited, there were military personnel standing guard.  Some were more vigilant looking than others, but they were all toting pretty serious weapons.  They are not all wearing the same uniform and I'm not familiar enough with the French military to know what different units they might be.

Versailles

Sacre Coeur.  There were six people patroling together and they were quite serious, signaling each other as they slowly advanced up the steps of the cathedral.