The extent of the fire is uncertain . According to Tacitus , who was nine at the time of the fire , it spread quickly and burned for over five days . It destroyed three of fourteen Roman districts and severely damaged seven . The only other historian who lived through the period and mentioned the fire is Pliny the Elder , who wrote about it in passing . Other historians who lived through the period ( including Josephus , Dio Chrysostom , Plutarch and Epictetus ) make no mention of it in what remains of their work .