Not surprisingly the line number 1 is the first line being from Porte de Vincennes to Porte Maillot. The metro opened on 19 july 1900. The system has 15 lines and 199 km (124 miles) of track. There are 368 stations (not including RER stations), 87 of these being interchanges between lines. Every building is within 500 metres of a metro station. There are 3500 cars which transport approximately 6 million people per day.
That’s why I like the line number 1. The cars pass from Grand Arche the La Defense to Château de Vincennes. The cars pass to some beautifull station, for example there is Louvre ambiance(museum ambiance) in Louvre-Rivoli,
The Châtelet station is my favourite too. When summer comes, many qualified musicians sing and play in this station. Châtelet has the longest interconnecting passageway between lines, with a 600-foot long moving sidewalk.