What does Robert Macfarlane think about every time he heads underground? This is the fateful question the readers of his books have to think about when flipping through the pages. The British author confessed to the audience at Palazzo San Sebastiano his profound interest for what is under our feet, in his conversation with writer and professor Davide Longo. This magnetism started in 2010, he said, when three news reports made us remember that there is a whole other world, which is mostly undiscovered, underneath the soil. The first was the Haiti earthquake, then the eruption Eyjafjallajökull in Iceland and, finally, the news that several Chilean miners were trapped in a cave. At the exact moment when the miners were rescued and freed from the darkness of the underworld, Macfarlane started to write his book Underland. It took him eight years to complete this work, which was published in 2019.

The author described how the mysterious world presented in Underland, a long descent toward the centre of the earth that he made in many countries around the world such as Italy, the United Kingdom and France. It was in Paris that Macfarlane went through an experience that was later retold in Underland: in stark opposition to the idea we have of the City of Lights, he stayed for two days and half in what he called “The City of Shadows”, the underground city beneath Paris, made up of streets and buildings, whose floor plan was drawn by clandestine cartographers. In this and in all the other trips he made, Macfarlane admitted to the audience the need for a companion, a Dantesque Virgil to show him the way into (and out of) the labyrinthine underground tunnels.