15 And thus shalt thou make it: let the length of the ark be three hundred cubits, the breadth of it fifty cubits, and the height of it thirty cubits.
Genesis 6:15 Cross References - Darby
Genesis 7:20
20 Fifteen cubits upward the waters prevailed; and the mountains were covered.
Deuteronomy 3:11
11 For only Og the king of Bashan remained of the residue of giants: behold, his bedstead was a bedstead of iron; is it not in Rabbah of the children of Ammon? its length was nine cubits, and its breadth four cubits, after the cubit of a man.