Paris Tourist Bus Map ( Click the map to enlarge it! )
Since the Metro is primarily structured around a hub-and-spoke model, there are some journeys for which it can be quite inefficient, and in these cases, it is worth seeing if a direct bus route exists, despite the complexity of the bus network. A bus ride is also interesting if you want to see more of the city. The Parisian bus system is quite tourist-friendly. It uses the same single-ride tickets and Carte Orange as the Métro, and electronic displays inside each bus tell riders its current position and what stops remain, eliminating a lot of confusion.
These same payment devices are also valid in the Noctilien, the night bus. Night buses run regularly through the central hub at Chatelet to outlying areas of greater Paris. There is also a circle line connecting the main train stations. It pays to know one's Noctilien route ahead of time in case one misses the last Métro home. Women travellers should probably avoid taking the Noctilien on their own to destinations outside Paris.
Another option for travelers who want to see the sights of Paris without a stop on every street corner is the Paris L'Opentour Bus, an open-topped double decker bus that supplies headsets with the most up to date information on the attractions in Paris. Your ticket is good for four routes ranging in time from 1-2 h. Get off when you want, stay as long as you need, get back on the bus and head for another site. You can purchase tickets at the bus stop. A one-day pass is 25 Euro for adults and 15 Euro for children. A two-day pass is 32 Euro for adults or 15 Euro for children.