Read the following text to answer the question.

Paris   

    Paris is the capital of a European nation, France. It is also one of the most beautiful and most famous cities in the world.

    Paris is called the city of Light. It is also an international fashion center. What stylish women are wearing in Paris will be worn by women all over the world. Paris is also famous for its world center of education. For instance, it is the headquarters of UNESCO, the United Nations Educational, Scientific and Cultural Organization.
 
    The Seine River divides the city into two parts. Thirty-two bridges cross this scenic river. The oldest and perhaps the most well-known is Pont Neuf, which was built in the sixteenth century. Sorbonne, a famous university, is located on the left bank (south side) of the river. The beautiful white church Sacre Coeur lies on the top of hill called Montmartre on the right bank (north side) of the Seine.

    There are many other famous places in Paris, such as the famous museum the Louvre as well the cathedral of Notre Dame. However, the most famous landmark in this city must be the Eiffel Tower.

    Paris is named after a group of people called the Parisii. They built a small village on an island in the middle of the Seine River about two thousand years ago. This island is called lie de la Cite. It is where Notre Dame located. Today around eight million people live in Paris area.  

What is the oldest and most well known part of the city?