Dante's Inferni.

The Infernal journey through the first part of the afterlife, Hell, begins in a dark forest where Dante is threatened by three wild beasts. He's rescued by his hero Virgil at Beatrice's request. Virgil guides and protects Dante on his dark journey descending circle-by-circle and their subdivisions to the center of the Earth where Lucifer resides, and out into Purgatory.