We spent our last full day in Paris exploring the Ile de la Cite, one of the oldest parts of the city and home to Notre Dame Cathedral. It was Palm Sunday so we saw a number of people carrying small branches (no palm trees in northern France). We had to pass through a security checkpoint to cross the bridge to the island. The French police and military are very visible around tourist and transportation centers, often carrying potent-looking machine guns. They do a good job of keeping the country safe.
The line to enter Notre Dame was long but it seemed to be moving fast so we took our place in line. In fact, it only took about ten or fifteen minutes to enter the cathedral. The building is spectacular, well worth seeing.
We walked around the Ile de la Cite and found a restaurant with a few small tables on a back street. It was nice to escape the hustle and bustle of Notre Dame. But when we walked around the block after lunch we discovered that we ate at the back patio of a much larger restaurant directly across the street from Notre Dame. So much for avoiding the Paris tourist circuit!
We finished the day by exploring the Conciergerie, a Gothic riverside fortress that was used as a prison by the French revolutionaries in the 18th century. Marie Antionette was held in the prison before she was led off the the Place de la Concorde to be beheaded.