Ezra 6:4

6:4 with three layers of large stones and one layer of timber. The expense is to be subsidized by the royal treasury.

Ezra 8:15

The Exiles Travel to Jerusalem

8:15 I had them assemble at the canal that flows toward Ahava, and we camped there for three days. I observed that the people and the priests were present, but I found no Levites there.

Ezra 10:8

10:8 Everyone who did not come within three days would thereby forfeit all his property, in keeping with the counsel of the officials and the elders. Furthermore, he himself would be excluded from the assembly of the exiles.