Five years ago, the S-1078B tunnel boring machine from the manufacturer Herrenknecht was christened the catchy name “Steffie Orbival” in front of several thousand onlookers and sunk in the Paris underground. The ceremony marked the starting point for the largest infrastructure project in Europe: the “Grand Paris Express”. This is a new subway network with 68 stations and four lines with autonomous trains. A project of the century, for which the French state is investing 35 billion euros and which will double the underground rail network in the metropolis by 2030, making it the largest metro network in Europe. A project of superlatives, which differs from major German projects such as BER or Stuttgart 21 in one respect: progress is being made.