The 2018 Ronald Syme Lecture was delivered by Professor Kathleen Coleman, James Loeb Professor of the Classics at Harvard University, on 1st November. The lecture was introduced by Wolfson College President Sir Tim Hitchens. After much jockeying between Rome and Parthia for control of Armenia, the Romans agreed to the reinstatement of the Parthian prince, Tiridates, on the Armenian throne, on condition that he be crowned at Rome by Nero. A surviving fragment of the Roman History of Cassius Dio recounts the remarkable nine-month journey undertaken by Tiridates, his wife, and their retinue of thousands overland from Armenia to Italy, and their ensuing detour to the Bay of Naples, where they were treated to a spectacular display in the arena at Puteoli. This episode tends to be overlooked in favor of the subsequent coronation in Rome. But the more one thinks about it, the more intriguing the detour becomes. This paper suggests reasons, diplomatic and otherwise, for the apparently illogical choice of route and the reception that was laid on for Tiridates at the end of it.