This is the marker for the Iron Age city-gates of Megiddo. It reads (in part):
Megiddo became an Israelite city sometime between the 10th and 9th centuries B.C., and functioned as an administrative center for the fertile Jezreel Valley. Some time later, a massive wall (1) and a monumental city-gate (2-4) were built. According to one opinion, the gate dates to the reign of Solomon (10th c. B.C.). Other scholars postdate the gate to the reign of either Ahab (9th c.) or Jeroboam II (8th c. B.C.).
In the Assyrian period (732-630 B.C.), the inner gatehouse was replaced by a two-chambered gate, whose remains can be seen on top of the older gatehouse.
“And this is the account of the forced labour which king Solomon levied to build the house of the Lord, and his own house and the millo and the wall of Jerusalem and Hazor and Megiddo and Gezer.” (1 Kings 9.15)