In the summer of 26 AD, Roman Emperor Tiberius left the city of Rome and chose to self-exile in Campania for a remarkable 11 years, a decision that remains puzzling. Since 21 AD, Tiberius had frequently retreated from public life, residing in various locations, with the longest stay being on the island of Capri. There, he managed state affairs through letters, only briefly returning to Rome on a few occasions. The reasons behind Tiberius's retreat are widely debated; some suggest it was influenced by the machinations of Sejanus, others point to the grief following the death of his son, while some believe he was forced to leave due to his mother's domineering nature. However, none of these explanations fully account for his eight-year seclusion. What secrets lie behind Tiberius's self-imposed exile remains an enduring historical mystery.