The haunting image of ‘twin cities’ in all its destabilising connotations, from the Gothic sense of doubling to the image of the World Trade Center, reveals how death permeates the urban landscape with the sense of the unknown, the unexpected and the unseen. In antiquity, the underground as a burial space for the dead, from Egyptian tombs to the Roman Catacombs, was predicated on the sacred belief that the afterlife below was just as important, if not more crucial, than the lived experience above. Indeed, the elaborate architecture of underground altars and temples in these civilisations attests to the power of the belief that the house of the living is but a ‘temporary abode’.