Quran 18:93 from Surah Al-Kahf on Divine Marvels.
حَتَّىٰٓ إِذَا بَلَغَ بَيۡنَ ٱلسَّدَّيۡنِ وَجَدَ مِن دُونِهِمَا قَوۡمٗا لَّا يَكَادُونَ يَفۡقَهُونَ قَوۡلٗا
English translation: Until when he reached between the two mountains he found besides them besides them a community not who would almost understand (his) speech
Transliteration: hatta idha balagha bayna al-sadayni wajada min dunihima qawman la yakaduna yafqahuna qawlan