Here are the points of interests in Paris and how to get to them by public transportation. We will use Châtelet – Les Halles RER Station as the starting point since it is one of the main hubs and it has 3 RER Lines crossing it.
Arc de Triomphe - take RER A to Charles de Gaulle - Étoile Station
Champ de Mars - take RER B to Saint-Michel Notre Dame Station then transfer to RER C to Champ de Mars / Tour Eiffel Station
Champs Elysées-Etoile - take RER A to Charles de Gaulle - Étoile Station then walk about a half-mile
Disneyland Paris and Walt Disney Studios - take RER A to Marne-la-Vallée / Parc Disneyland Station
Eiffel Tower - take RER B to Saint-Michel Notre Dame Station then transfer to RER C to Champ de Mars / Tour Eiffel Station
Fountain of the Innocents - about a half-mile walk from Châtelet – Les Halles RER Station
Grand Palace - take RER B to Saint-Michel Notre Dame Station then transfer to RER C to Invalides Station then walk about a half-mile
Invalides - take RER B to Saint-Michel Notre Dame Station then transfer to RER C to Invalides Station
Louvre Museum/Musée du Louvre - about a mile walk from Châtelet – Les Halles RER Station
Luxembourg Gardens - take RER B to Luxembourg Station
Moulin Rouge - take RER B to Gare du Nord Station then walk about a mile
Musée des Arts - about a mile walk from Châtelet – Les Halles RER Station
Notre Dame Cathedral - take RER B to Saint-Michel Notre Dame Station
Opéra - take RER A to Auber Station
Orsay Museum/Musée d'Orsay - take RER B to Saint-Michel Notre Dame Station then transfer to RER C to Musée d'Orsay Station
Palace of Versailles/Château de Versailles - take RER B to Saint-Michel Notre Dame Station then transfer to RER C to Versailles - Rive Gauche / Château de Versailles Station
Pantheon - take RER B to Luxembourg Station then walk about a half-mile
Sacré-Coeur Basilica - take RER B to Gare du Nord Station then walk about a mile
Saint Jacques Tower - about a half-mile walk from Châtelet – Les Halles RER Station
Saint Michel Fountain - take RER B to Saint-Michel Notre Dame Station
Statue of Liberty - take RER B to Saint-Michel Notre Dame Station then transfer to RER C to Avenue du Président Kennedy Station
Trocadéro - take RER B to Saint-Michel Notre Dame Station then transfer to RER C to Champ de Mars / Tour Eiffel Station then walk about a mile
Below is a map of Paris' RER Lines and Stations: