I step into the metro carriage. It is quiet, as expected on a cold November afternoon. I ride the line 11 almost all the way to the ring road surrounding the city, which squeezes its 2.1 million inhabitants into a space suited for half that number. The metro line is faster than those I’m used to; the carriage sways uncertainly, as if it could topple at any moment. There’s a woman sitting opposite eating chicken wings from a grease-stained bag and the man perched next to me is watching an American sitcom with French subtitles, smiling slightly at his large phone screen.