Al-Kahf - 18:83

وَيَسْأَلُونَكَ عَن ذِي الْقَرْنَيْنِ قُلْ سَأَتْلُو عَلَيْكُم مِّنْهُ ذِكْرًا
[18:83]
And they ask you about Zulqarnain. Say: I will recite to you an account of him.
They ask thee concerning Zul-qarnain. Say, "I will rehearse to you something of his story."
They will ask thee of Dhu'l-Qarneyn. Say: I shall recite unto you a remembrance of him.