We really wanted to visit Paris, but a day tour from a cruise ship was a huge mistake! LeHavre, where our ship docked was a 3 hour bus ride each way to visit Paris, that only left 4 hours within the city. That truly isn't enough time to see, experience or absorb anything.
Also, I was on my 2nd day of my head and chest cold and I was out of medicine. I felt miserable and sluggish- no condition to try and visit a city as vast as Paris.