Paris is one of my most favorite cities.  And, one of the best ways to easily get around town is by using the L'Open Tour hop-on, hop-off bus.  You can purchase a 1 or 2 day tour with 4 tour routes (29 Euros/1 day; 32 Euros/2 days).  There are 50 stops total.  Like other hop-on hop-off buses, there is an enclosed bottom deck with an open air top deck.  Buses come every 10-30 minutes and you receive earphones for a guided tour.  You can purchase the tickets as you get on the bus.  This is also...