In 2002, a group of geographers attempted to map the world’s wildernesses. Every square kilometre of land was given a score between zero and seventy-­two, reflecting the level of human influence. Many regions occupied by indigenous populations scored a perfect zero, but Antarctica, the one continent of undisputed emptiness, was left off the dataset. Meanwhile, the only location to score the maximum seventy-two was not Tokyo, Shanghai or New York City; it was the small Texan city of Brownsville on the southern US border.

These questionable scientific efforts suggest that if wilderness is characterised by certain geographical features – extreme heat or cold, dizzying altitude or daunting remoteness – it is also a feeling. In Cal Flyn’s words, that feeling is ‘the sense of communing with all that is not human, a thinning of the skin’. Her new book, The Savage Landscape, asks why humans respond this way towards wilderness, and why some people seek that feeling again and again.

The book is structured around the author’s journeys to a dozen different wildernesses. These include the rocky corners of the Sinai desert in Egypt, the bear-filled forests of Transylvania and the high valleys of Dolpo, Nepal. She also explores historical and mythical wildernesses, from the great expanses of mountain or