(Al-Mursalath) 77 : 27
وَجَعَلْنَا فِيهَا رَوَاسِيَ شَامِخَاتٍ وَأَسْقَيْنَاكُمْ مَاءً فُرَاتًا
And We made in it mountains as towering and firm, and provided for you sweet, clear water.
See explanation 23: 18-20 and 56: 8-70.