What was the secret of the Trojan horse?

The story of the battle of Troy is told in Homer’s poem the Iliad. About 1200 B.C. a huge, hollow, wooden horse was felt outside the great walls of the mighty city of Troy. Inside, a group of armed men lay hidden. For nine years Troy had been besieged by the Greeks. It appeared they had now abandoned the siege, and sailed away, leaving the horse behind them. The Trojans dragged it within the walls. Night fell, and the city slept. From the horse’s trapdoor the Greeks slid, killed the Trojan sentries, opened the city gates, and signaled to the waiting fleet. The Trojans were soon defeated and their city reduced to a smoking ruin.