When you think of Paris you think of the Eiffel Tower, Poodles, French Sticks, Cheese, the Moulin Rouge and of course the Notre Dame Cathedral. This magnificent Gothic cathedral dates back to 1166 during the reign of Louis VII and was completed around 1345. The cathedral is so important to Paris that all distances from Paris are measured from a stone in front of the Notre Dame This stone is known as Point Zero. The cathedral is open to the public daily between 7:45AM and 6:45PM except during mass times and there is a great little market outside the Notre Dame selling religious artifacts, books and food.
Official Site: http://www.cathedraledeparis.com/EN/0.asp
Map showing the Notre Dame