Quran 18:83

وَيَسْـَٔلُونَكَ عَن ذِى ٱلْقَرْنَيْنِ ۖ قُلْ سَأَتْلُوا۟ عَلَيْكُم مِّنْهُ ذِكْرًا

And they ask you, [O Muhammad], about Dhul-Qarnayn. Say, "I will recite to you about him a report."

Translation · Saheeh International