I'm going to be in Paris on my own for a day. I'll arrive at the airport at 9am on a Monday and then have the whole day to do whatever I want. I've only been to Paris once before, when I was a child, so I'm looking for any advice on how best to plan the day to see everything.
I'd like to go up the Eiffel Tower, have a cruise down the Seine, visit the Louvre, and eat at the Ritz (only because I went to the London one a long time ago and it was such an amazing experience I'd love to see the Paris one). Is it realistic to do all of these things in one day? Or am I missing anything out that's a definite must see?