Ezra 6:15

15 The temple was completed on the third day of the month Adar, in the sixth year of the reign of King Darius.

Read Ezra 6:15 Using Other Translations

And this house was finished on the third day of the month Adar, which was in the sixth year of the reign of Darius the king.
and this house was finished on the third day of the month of Adar, in the sixth year of the reign of Darius the king.
The Temple was completed on March 12, during the sixth year of King Darius’s reign.