Year 317 (CCCXVII) was a common year starting on Tuesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Gallicanus and Bassus (or, less frequently, year 1070 Ab urbe condita). The denomination 317 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.