What physical evidence is there that Solomon existed?

Answer:

Isn't it amazing that people will cite historical documents and accept that someone like Julius Caesar or Sargon existed, but the Bible is skipped even though it is an ancient document? Now, if you are asking what additional proof there is of Solomon, we still can list a few.

Documents in the past were written on scrolls and sealed with a piece of clay stamped with the author's unique seal. Fires often destroy buildings that contain the scrolls, but the same heat bakes the clay seals turning them into pottery that are called bullae. In a small town in Israel, a number of bullae have been found dating to the 10th century B.C., showing that an extensive government operation existed during the period that Solomon lived. ["Discovery of official clay seals support existence of biblical kings David and Solomon, archaeologists say," Science Daily, 16 December 2014].

"Now this is the account of the forced labor which King Solomon levied to build the house of the LORD, his own house, the Millo, the wall of Jerusalem, Hazor, Megiddo, and Gezer. For Pharaoh king of Egypt had gone up and captured Gezer and burned it with fire, and killed the Canaanites who lived in the city, and had given it as a dowry to his daughter, Solomon's wife. So Solomon rebuilt Gezer and the lower Beth-horon and Baalath and Tamar in the wilderness, in the land of Judah, and all the storage cities which Solomon had, even the cities for his chariots and the cities for his horsemen, and all that it pleased Solomon to build in Jerusalem, in Lebanon, and in all the land under his rule" (I Kings 9:15-19).

"Archaeologists discovered similar building features at these three cities [Hazor, Megiddo, and Gezer] that conclusively date their construction to the 10th century BC; this is of tremendous importance for demonstrating the historical accuracy of the Biblical account of Solomon’s building projects. Archeologists discovered that each of these three cities built during the Solomonic period shared the same building features." [Sebastian Kettley, "'Confirms Bible account' Archaeology discoveries back King Solomon's reign, scholar claims," Express, 20 August 2020].

"Between 1957 CE and 1971 CE, archaeologist Yigael Yadin began excavations at two of the three cities mentioned in 1 Kings 9 (fully at Hazor and in a cursory investigation at Megiddo), which had gates supposedly built by King Solomon c. 960 BCE. Based on compared archaeological evidence from all three sites, which included Macalister's excavation report at Gezer from 1902–09 CE, Yadin concluded that the three city gates were designed by the same engineer (based on the same structural dimensions), built by the same workers (stylistically and methodologically from Phoenicia), and utilized the same material (they contained ashlar masonry quarried in Tyre). Additionally, in the 1860s CE, Charles Warren discovered a wall and courtyard in Jerusalem that were later found to be identical to the one in Megiddo and dating from the period of King Solomon." [John S. Knox, "Solomon", Ancient History Encyclopedia, 25 January 2017].

An extensive mining operation in Timna, dating to the time of Solomon's reign has been found [Philippe Bohstrom, "Did David and Solomon's United Monarchy Exist? Vast Ancient Mining Operation May Hold Answers," Haaretz, 21 November 2017].

Additional Resources:

• Dave Aeilts & Steve Law, "Have Solomon's Gates Been Found?" Patterns of Evidence, 26 January 2018.
• John S. Knox, "Solomon", Ancient History Encyclopedia, 25 January 2017. [Good summary of what has been found so far about Solomon.]