The old St. Peter's Basilica is consecrated by Pope Sylvester I.

Old St. Peter's Basilica was the church buildings that stood, from the 4th to 16th centuries, where St. Peter's Basilica stands today in Vatican City. Construction of the basilica, built over the historical site of the Circus of Nero, began during the reign of Roman Emperor Constantine I. The name "old St. Peter's Basilica" has been used since the construction of the current basilica to distinguish the two buildings.

Pope Sylvester I was the bishop of Rome from 31 January 314 until his death on 31 December 335. He filled the See of Rome at an important era in the history of the Western Church, though very little is known of his life.

November 18 is the 322nd day of the year in the Gregorian calendar; 43 days remain until the end of the year.