Which 1933 novel by C.S. Lewis follows a traveler through an allegorical landscape?

The Pilgrim's Regress is C.S. Lewis's 1933 allegorical novel about a character named John who travels through a symbolic landscape. The book was Lewis's first published work of prose fiction.

Its title deliberately recalls John Bunyan's The Pilgrim's Progress, but Lewis's book presents a modern philosophical and religious journey. John encounters figures and places representing ideas, movements, and competing approaches to meaning.

Lewis later said that the book's symbolism was not always easy for readers to identify. Unlike The Great Divorce, which is a shorter theological fantasy, The Pilgrim's Regress is structured as an extended allegorical journey and reflects Lewis's early development as a Christian author.