It's a few minutes past 8 a.m. and the Fabra i Puig metro station on Line 1 is overflowing. The train arrives—already quite full—and barely manages to absorb all the passengers on the platform, which is now clear. But the scene is short-lived. Seconds later, a new wave of people, practically a hundred, passes through the access gates and gets off onto the platform. A little while later, another group joins them. In a matter of minutes, the platform is packed again until another train arrives. The scene is reminiscent of the rhythm of queues at an amusement park or the impossible intersections of Tokyo, and it repeats itself tirelessly every 3 minutes. That is, the time it takes for the train to arrive during rush hour.