But change is coming – and on a huge scale. The venerable Paris Métro is about to get its most significant upgrade in decades with the arrival of the Grand Paris Express, a new 200-kilometer (120-mile) system that will add four lines and 68 brand-new stations to the network.

These will mainly be connecting suburban towns without passing through the densely populated city of Paris – adding outer rings to an underground map of Paris that has, until now, been made of 14 lines that only reach out from the center like spokes.