Narnia is the fictional world where most of C.S. Lewis’s Chronicles of Narnia stories take place. The name can refer both to the wider world and, in some contexts, to the central country within that world.
The seven-book series begins with The Lion, the Witch and the Wardrobe for publication purposes and concludes with The Last Battle. Its stories include talking animals, humans from Earth, dwarfs, giants, sea voyagers, and other magical beings.
Narnia is not the only land in the series. Readers also visit places such as Archenland, Calormen, the Lone Islands, and the underworld-like realm beneath the earth. These locations help show that Narnia belongs to a larger invented cosmos.
The name is sometimes confused with Aslan, who is Narnia’s lion ruler, or with Cair Paravel, a major castle. Those are different things: Narnia is the setting, Aslan is a central character, and Cair Paravel is a royal stronghold.