1 Kings 9:15

Millo] some part of the fortifications of Jerusalem is meant, perhaps a solid tower, but its place is not known. The LXX renders it by 'citadel,' and its importance is evidenced by its being so frequently rebuilt (1 Kings 11:27; 2 Chronicles 32:5). Hazor and Megiddo] Hazor, near Lake Merom, guarded the northern frontier, whilst Megiddo protected the approach to the plain of Esdraelon from the SW. Gezer] on the W. border of Ephraim, the modern Tell Jezer, 18 m. from Jerusalem. Gezer and Bethhoron (1 Kings 9:17) protected the valley of Aijalon.