Surah Al-Anbiya Verse 96

حَتَّىٰ إِذَا فُتِحَتْ يَأْجُوجُ وَمَأْجُوجُ وَهُمْ مِنْ كُلِّ حَدَبٍ يَنْسِلُونَ

Until when [the dam of] Gog and Magog has been opened and they, from every elevation, descend