The Great Fire of Rome causes widespread devastation and rages on for six days, destroying half of the city.

AD 64 (LXIV) was a leap year starting on Sunday of the Julian calendar, the 64th Year of the Anno Domini designation, the 64th year of the 1st millennium, the 64th year of the 1st century, and the 4th year of the 7th decade. At the time, it was known as the Year of the Consulship of Bassus and Crassus. The denomination AD 64 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.

The Great Fire of Rome began on 19 July 64 AD. The fire started in the merchant shops around Rome's chariot stadium, Circus Maximus. After six days, the fire was brought under control, but before the damage could be assessed, the fire reignited and burned for another three days. In the aftermath of the fire, nearly three quarters of Rome had been destroyed.

July 19 is the 200th day of the year in the Gregorian calendar; 165 days remain until the end of the year.