What object serves as a portal to Narnia in the first book?

A wardrobe serves as the portal to Narnia in the first book. Lucy Pevensie discovers the entrance while hiding inside an old wardrobe at Professor Kirke’s country house.

At first, Lucy thinks she is walking through an ordinary piece of furniture. Instead, she finds herself moving beyond the coats into a snowy forest, where a lamppost stands in the middle of the woods. There she meets Mr. Tumnus, a faun who tells her that she has entered Narnia.

The wardrobe becomes the story’s bridge between wartime England and the magical kingdom. Later, Peter, Susan, and Edmund also pass through it, joining Lucy in Narnia. The children eventually return through the same wardrobe, discovering that many years have passed in Narnia even though almost no time has passed in England.

The object is sometimes remembered as a generic door or magic mirror, but those belong to other fantasy stories. In Lewis’s novel, the portal is specifically a wardrobe. The idea was inspired partly by Lewis’s childhood imagination and by stories of magical passages hidden in ordinary rooms.