Paris is
so beautiful. If you have the means, I highly recommend going.
When I arrived at my hotel around 2 pm on Sunday, the receptionist called a colleague of his to confirm the arrangements for the room that was reserved for me. As he waited for said colleague to answer the phone, he pulled a glass of wine from under his desk and took a swig.
My room on the fifth floor had a balcony (actually two--one from the main room and one from the bathroom), which looked out on all the other beautiful buildings on the street.
Mostly I spent my time (the time not spent at math talks) walking around. I stopped in at Notre Dame and walked through the courtyards of the Louvre. I didn't go into the Louvre because it was only going to be open for another hour, rendering its €9 entry fee out of my budget. I walked up the Avenue des Champs Élysées, which, dominated as it was by megastores, was made worthwhile only by the Arc de Triomphe at the end, which was indeed impressive. Wandering back across the Seine, I followed the glittering lights to the Eiffel Tower.
Yesterday was the first meeting of the London-Paris Number Theory Seminar. My advisor gave a talk about the paper of his that I'm reading and there were two other talks also about generalizations of Serre's Conjecture. Jean-Pierre Serre himself attended the seminar.
Afterwards, I wandered around a bit more, getting mildly lost in lovely cobblestone back streets, discovering beautiful little bookstores that made me wish I knew French and a tiny Japanese import shop that I was allowed to peruse even though they were closed and had delicate pottery scattered everywhere.
I walked up past Moulin Rouge, which was surely the least interesting bit of Paris I saw while I was there, and then headed back to the Gare du Nord to catch the Eurostar back to London.