One of the most-visited cities in the world probably has more things that'll make you go “oh look, it's...” than any other place. The Eiffel Tower, the Pantheon, arc de Triomphe etc. etc. Most are only ten kms from the others, but you'll still be stretched to see EVERYTHING. Getting around's easy on the RER - suburbs mainly and Metro - city mainly and buses. To get there fast, an RER can get you the city from Charles De Gaulle Airport.