Macfarlane, who won the E.M. Forster Award for Literature in 2017, is primarily known as a nature writer, but it is not a term he is altogether comfortable with, especially regarding “Underland.” “The nature here is rock and ice and time and nuclear waste and human activity,” he said. “So if it is nature writing, then it is a dark kind of nature writing, but I’m quite happy for it not to sit easily in a genre.”

In “Underland,” as in his previous books, he insists on experiencing things for himself. He navigates precarious underground passageways in the Paris catacombs or ancient burial tombs in the Mendips of Somerset. Gradually he became fascinated by “the idea that claustrophobia might possess this vicarious power to move people, grip them,” he said. “The body comes to know places in ways that can’t be known by reading or remote-sensing.”

When he was younger, he was an avid rock climber, though he qualifies this with self-deprecation: “I was very bad at it, but I was quite bold, and that’s a bad combination.” After an aborted Alps expedition — “I just reached a point on a knife edge at a ridge where it was impossible to proceed” — he has dialed back. He also has his wife, the writer and China scholar Julia Lovell, and their three children, Lily, Tom and Will, to consider.

Macfarlane grew up in rural Nottinghamshire, but his love of nature and landscape bloomed when his parents began taking the family on walking holidays in Scotland. “That was the country that’s drawn me back and back as a writer and as a walker and a climber,” he said. “‘Underland’ is the first book I’ve ever written that has no Scotland in it.”

Image Credit... Alessandra Montalto/The New York Times

Altogether there have been nine books. To his surprise the one that has had the most impact is a children’s title, “The Lost Words.”

Published in 2017, it began when Macfarlane and the British artist Jackie Morris were told that the latest edition of the Oxford Junior Dictionary had dropped nature words like “acorn,” “dandelion” and “kingfisher” in favor of technological terms. Together they created “The Lost Words” as a book of poetry or “spells,” with his writing and her illustrations.