Which 1950 C.S. Lewis novel begins with four children entering another world through a wardrobe?

The 1950 C.S. Lewis novel beginning with four children entering another world through a wardrobe is The Lion, the Witch and the Wardrobe.

The children are Peter, Susan, Edmund, and Lucy Pevensie. Lucy discovers the passage into Narnia while hiding in a wardrobe during a game at a country house. In Narnia, she meets the faun Mr. Tumnus and learns that the land is trapped in a winter imposed by the White Witch.

The novel introduces major Narnian figures including Aslan, the Pevensie children, and the White Witch. It was the first Narnia book published, although Lewis later wrote The Magician’s Nephew as a chronological prequel to the events of the series.

The wardrobe opening is one of the book’s most recognizable scenes, but the novel’s central setting is the wider land of Narnia, not the house or the wardrobe itself. Lewis dedicated the book to his goddaughter, Lucy Barfield.