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The Gates of Nikanor
Different explanations for the calling of the gates "Nikanor"
According to the first version, which appears in the Talmud, the gates are named after the person who donated them. That person was Nikanor of Alexandria, who scarified himself for bringing the gates to the Temple, as the Talmud states: "A miracle occurred to the gates of Nikanor".
The other version, which is less known, is brought up in the Talmud Yerushalmi, and reads as follows: "Why are the gates named the Gates of Nikanor? Because Nikanor, the King of the Greeks, stood in front of the gates to the temple and waved his hands toward it and said: 'When will this Temple fall in my hands so that I can destroy it?' and when the Hasmoneans triumphed over the Greeks and conquered the city, they caught Nikanor and cut off his hands and his legs and hanged him in front of the gates, and called the gates 'the Gates of Nikanor'."
The Gates of Nikanor were the only gates leading to the Temple that were not gold-coated, because their color was similar to that of gold, and because Nikanor had sacrificed himself for the sake of bringing them to the holy City.