https://www.youtube.com/watch?v=uTnu5yUHDps
https://en.wikipedia.org/wiki/Copenhagen_Metro#Service
https://en.wikipedia.org/wiki/Copenhagen_Metro#Stations "The deep-level stations are built as rectangular, open boxes 60 metres (197 ft) long, 20 metres (66 ft) wide and 20 metres (66 ft) deep."
A ride on Copenhagen's M4 metro line https://www.youtube.com/watch?v=J1i8G5FhPFY
Copenhagen's Metro system blazed a trail in metro automation, and still stands as one of the best in the world. https://www.youtube.com/watch?v=2sx4BPbOASg
