Roman armies relied heavily upon sophisticated engineering techniques such as putting arches into the tunnels they built during sieges. The Trustees of the British Museum, CC BY-SA For an invader who does not possess a thorough map of the subterranean passages, this can present a nightmare scenario, leading to massive personnel losses, plummeting morale and an inability to finish the conquest of their urban objective – all factors that may have factored in Putin’s decision not to send troops underground in Mariupol.Īssyrian engraving of the siege of an Egyptian fort. Such networks allow small units to move undetected by aerial sensors and emerge in unexpected locations to launch surprise attacks and then essentially disappear.

Indeed since the war began in February, reports have emerged of Ukrainian defenders using underground tunnel networks in efforts to deny Russian invaders control of major cities, as well as to provide sanctuary for civilians.Īs an expert in military history and theory, I know there is sound thinking behind using tunnels as both a defensive and offensive tactic. While Putin’s back-up plan – to form a seal around trapped Ukrainian forces and wait it out – is no less brutal and there are reports that Russians may still have mounted an offensive on the site, Putin’s hesitancy to send his forces into a sprawling network of tunnels under the complex hints at a truth in warfare: Tunnels can be an effective tool in resisting an oppressor.

“There is no need to climb into these catacombs and crawl underground,” he told his defense minister on April 21, 2022, ordering him to cancel a planned storming of a steel plant in the besieged Ukrainian port city of Mariupol. Faced with the prospect of sending Russian troops into subterranean combat, Vladimir Putin demurred.

Beneath a steel sky trapped