Some of the most interesting contemporary authors are travelling existentialists – wanderers in thought who also physically wander, from Iain Sinclair to W G Sebald to Rebecca Solnit. In these days of publishing collapse and risk aversion, the journey or quest seems to soothe editorial anxieties about reason, plot and conveyable purpose, allowing the author to muse at will, to experiment with form and tempo, to elide fact and fiction. As Sinclair has an editor say at the beginning of Hackney, That Rose-Red Empire, ‘Lit-fic’s a dead duck … Carry on with the same book but pepper it with real names, actual locations … We’ll squeeze you into the travel sections.’

In Wanderlust: A History of Walking (2000), Solnit explains: ‘Though the history of walking is, as part of all these fields and everyone’s experience, virtually infinite, this history of walking I am writing can only be partial, an idiosyncratic path traced through them by one walker, with much doubling back