
The Eiffel Tower’s hours of operation are 9:30 to 23:00 daily and are extended to 9:00 to 00:00 in summer. You can walk to the second floor for 5 Euros or ride the elevator for 9 Euros. The Lift to the top is 15 Euros. I am cheap so every time I have went I have used the stairs, but any sane person should take the elevator.
Not that I advise it, but here is how you can fit the Musee d’Orsay, the Palace of Versailles, the Eiffel Tower, the Arc De Triomphe, and the Champs Elysee, into one dizzying day.
Begin your morning at the impressionist paradise Musee d’Orsay (almost everyone says it’s their favorite Parisian museum). After about 2 hours of enjoying masterworks by Frédéric Bazille and Emile Bernard in the grandly re-purposed railway station, proceed to the d’Orsay Metro Station and take RER C-line to Versailles (about 40 minutes). Walk to the Palace of Versailles and spend the afternoon and evening marveling at one of the great architectural and botanic treasures on the planet and understanding why the proletariat revolted against King Louis XVI. The château, which houses the epoch-of-decadence Hall of Mirrors, the King’s Grand Apartments, and the Museum of the History of France, is open until 6:30 PM and the expansive verdant gardens and parks are open until 8:30 PM.

When visiting the Palace at Versailles, consider buying the “passport” which will get you full access to all the Palace tours, grounds, Trianon palaces, and the proletariat maddening Marie-Antoinette’s Estate. From April to October, the “passport” also includes the Musical Fountain and Musical Gardens shows. All other exhibitions are also included. It’ll be one of the most rewarding 18 Euros ever spent.
If you time it right, during your return to Paris, you can jump off at the Eiffel Tower station, pay 15 Euros for the ride to the top of Paris (actually, because it adorns a huge hill the Sacre Coeur is higher) and catch a memorable sunset over the cityscape. Continue to the world’s grandest shopping and dinning boulevard, the Champs Elysee, for a late dinner, and if you missed it, continue west on the Champs Elysee to the the Arc De Triomphe.
If the mood strikes you pop into one of the many Parisian bakeries for a quick desert or catch a flick with the French, who watch movies at a higher intensity than anyone else.