Albert Barnes Commentary 1 Kings 9:15

"And this is the reason of the levy which king Solomon raised, to build the house of Jehovah, and his own house, and Millo, and the wall of Jerusalem, and Hazor, and Megiddo, and Gezer." — 1 Kings 9:15 (ASV)

Levy - See the marginal reference note.

Millo - See the note on 2 Samuel 5:9. The Septuagint commonly renders the word hē akra, “the citadel,” and it may possibly have been the fortress on Mount Zion connected with the Maccabean struggles (13:49-52). Its exact site has not been determined.

And the wall of Jerusalem - David’s fortification (2 Samuel 5:9; 1 Chronicles 11:8) had been built hastily and, fifty years later, had fallen into decay. Solomon, therefore, had to repair the breaches of the city of David (1 Kings 11:27).

Hazor, Megiddo, and Gezer were three of the most important sites in the Holy Land. For the first two places, see the marginal references and notes. Gezer was a major city in the south, situated on the great maritime plain, and it commanded the ordinary line of approach from Egypt along this low region. Its importance is clear from Joshua 10:33 and 12:12. The site is near Tell Jezer, now marked by Abu Shusheh. Although Gezer was within the territory of Ephraim (Joshua 16:3) and assigned to the Kohathite Levites (Joshua 21:21), it had not yet been conquered from its original inhabitants. They continued to live there, apparently as an independent people, until Solomon’s time (1 Kings 9:16).

Pharaoh captured Gezer before his daughter’s marriage to Solomon and gave it for a present—that is, as a dowry. Although husbands in the East generally pay for their wives, a dowry is given in some cases. For example, Sargon gave Cilicia as a dowry with his daughter when he married her to Ambris, king of Tubal, and the Persian kings seem to have generally given satrapies or other high offices as dowries to their daughters’ husbands.