Just south of Maastricht in the Netherlands, the Sint Petersburg tunnels were developed by the Romans, who quarried the soft marlstone, creating an underground system that provided refuge during the many occasions when Maastricht found itself under attack. During the Second World War, the whole complex became an underground city, housing a well, storeroom, chapel, kitchen, bakery, and a pen for livestock. Comprising a vast number of separate passages – up to 20,000 – the complete system adds up to 200km, stretching into nearby Belgium.
Underground cities are always places of retreat when life above-ground becomes threatened, whether seen in the early Christian tunnels beneath Cappadocia in Turkey, the Chislehurst caves on the edge of London, or nuclear bunkers in countless secret – and not-so secret – locations. In these places, underground space reverts to its primal role of providing safety, originating from the time when we sheltered in caves from predators or perhaps in the enclosed world of the nine months before we are born. It is in literature and film that the underground city continues to be presented as an imagined future for civilization, once the threats above ground become unendurable: from the subterranean factory in H. G. Wells’s The Time Machine (1895) and Fritz Lang’s Metropolis (1927); the hermetically-sealed space of E. M. Forster’s The Machine Stops (1909); the nightmarish prison of Twelve Monkeys (1995); to the only free place left in the cyberspace of The Matrix (1999).