Travelling a thousand miles and across three billion years, Christopher Somerville (walking correspondent of The Times and author of Coast, The January Man and Ships of Heaven) sets out to interrogate the land beneath our feet, and how it has affected every aspect of human history from farming to house construction, the Industrial Revolution to the current climate crisis. In his thousand-mile journey, Somerville follows the story of Britain's unique geology, travelling from the three billion year old rocks of the Isle of Lewis. Demystifying the sometimes daunting technicalities of geology with humour and a characteristic lightness of touch, Somerville's book tells a story of humanity's reckless exploitation and a lemming-like surge towards self-annihilation but also shows seeds of hope as we learn how we might work with geology to avert a climate catastrophe.