Just look at this gif of the shanghai metro growing from nothing in 1993 to the largest metro system in the world in 2015: https://upload.wikimedia.org/wikiped

Just look at this gif of the shanghai metro growing from nothing in 1993 to the largest metro system in the world in 2015: https://upload.wikimedia.org/wikipedia/commons/9/9f/SHM_evolution_mid.gif https://upload.wikimedia.org/wikipedia/commons/9/9f/SHM_evol...