Al-Kahf 97

فَمَا ٱسْطَٰعُوٓا۟ أَن يَظْهَرُوهُ وَمَا ٱسْتَطَٰعُوا۟ لَهُۥ نَقْبًا ﴿٩٧﴾

Fama istaAAoo an yathharoohu wama istataAAoo lahu naqban

So they [Ya'juj and Ma'juj (Gog and Magog)] were made powerless to scale it or dig through it. The Noble Quran