Fifteen cubits upward did the waters prevail; and the mountains were covered.
Referenced Verses
Ps 104:6 : 6 Thou coveredst it with the deep as with a garment: the waters stood above the mountains.
Jer 3:23 : 23 Truly in vain is salvation hoped for from the hills, and from the multitude of mountains: truly in the LORD our God is the salvation of Israel.