The Birth of Jesus and the Adoration of the Shepherds.
The reason for the journey to Bethlehem:
Related Commentaries of Luke 2:1
Luke 2:1-2
1 And it came to pass in those days, that there went out a decree from Caesar Augustus, that all the world should be taxed.a
2 (And this taxing was first made when Cyrenius was governor of Syria.)