In book 6 of the Aeneid, Aeneas and his fleet finally arrive in Italy, where they land at Cumi, home of the Sibyl, a priestess of Apollo who sees the future. He makes the required sacrifices and promises to build a new temple for the Sibyl when he finds his fated city in Latium. The god Apollo speaks through the Sibyl saying that Aeneas will achieve his fate, but after a terrible war. Aeneas must visit the underworld and to do so he has to find and pluck a golden bough that that's precious to Proserpina, queen of the dead, from a tree deep in the forest. Aeneas appeals to his mother, Venus, who sends doves to guide him.
He enthusiastically tears the branch off the tree. The Sybil and Aeneas enter the cave leading to the underworld and approach the river Acheron, which dead souls must cross to enter. Aeneas spots a number of men from his fleet who have died, but they cannot cross because their bodies remain unburied on Earth. The Sybil assures Aeneas is Aeneas'pilot that strangers will soon bury his body. Charon, ferryman of the dead, challenges them, but the golden bow allows them to pass into the underworld.
Now in the underworld, each type of dead soul has its own area, and the marshes around the river Styx hold the souls of the tragic dead. Infants, suicides, and those killed by cruel love. Aeneas sees the spirit of Dido and tries to talk to her, but she angrily gives him the cold shoulder and storms off to her first husband, who's a also there. After encountering both Trojan and Greek heroes, Aeneas and the Sybil use the golden bow to enter Elysium.
In the peaceful Elysian fields, the soul of Anchises shows Aeneas their descendants waiting to be reborn into the world. Among many others, Ascanius points out Romulus, founder of Rome, Julius Caesar, and Caesar Augustus, Rome's ruler at the time. He previews centuries of Roman history and charges Romans to rule with all your might. your power, the people of the earth.
Then Aeneas and the Sybil return to the world of the living through the ivory gates of sleep. The golden bow that allows Aeneas to access the underworld cannot be picked if it's not fated to be, making it a symbol of the inevitability of Aeneas's extraordinary fate. The Elysian fields inhabited by souls waiting for reincarnation allows Aeneas's father to show his son the great leaders who will come after him.
And Cayces describes figures mostly historical, from the founding of Rome up to Virgil's current ruler, Caesar Augustus. Virgil here mixes future, present, and past verb tenses to skillfully create a sense of people and events that are still to occur in Aeneas'time but would be known to Roman readers of the Aeneid as historical. This sense of the past as present and future contributes powerfully to the sense of Rome's destiny with a future as glorious as its past.