2 Chronicles 3:2

And he began to build in the second day of the second month, in the fourth year of his reign.

Solomon commenced construction of the temple on the second day of the second month in the fourth year of his reign. That starting point fell 480 years after Israel's departure from Egypt. The work was undertaken at Jerusalem on Mount Moriah, the spot where the Lord had appeared to David his father, on the threshing floor of Ornan the Jebusite which David had made ready.