300

The year 300 started on Monday, January 1, and ended on Tuesday, December 31. It was a leap year (in the Julian calendar, although it would not have been a leap year in the proleptic Gregorian calendar). Also, it was the last year of the 3rd century.

Calendar with holidays
Holidays:
 * New Year's Day: Monday, January 1
 * Leap Day: Thursday, February 29
 * Halloween: Thursday, October 31
 * New Year's Eve: Tuesday, December 31