What was Noah's Ark made of according to the Book of Genesis?

According to the Book of Genesis, Noah's Ark was made of gopher wood.

Genesis 6:14 instructs Noah to make the ark from “gopher wood” and to cover it inside and outside with pitch. The Hebrew term translated as “gopher wood” is unusual: it appears only in this passage, so its exact botanical meaning is uncertain. Many English translations retain the transliteration rather than identifying a modern tree species.

Because the word is obscure, it is not the same as the better-known biblical woods used elsewhere. Acacia wood, for example, is associated with parts of the Tabernacle in Exodus. Cedar is frequently mentioned in biblical descriptions of construction, but Genesis does not call the ark cedar.

The same verse also gives the ark's basic construction instructions: compartments, or rooms, were to be made inside it, and pitch was used to make it watertight. Thus “gopher wood” is the specific traditional answer, even though scholars cannot securely identify the wood today.