In the Epic of Atrahasis, bitumen was used to seal the flood boat. The Mesopotamian text describes the boat being waterproofed with bitumen, a naturally occurring petroleum-based material used widely in the ancient Near East.
Atrahasis is an Akkadian flood story preserved on clay tablets, with important copies dating to the second millennium BCE. The god Enki warns Atrahasis of a coming flood and tells him to build a boat. The narrative includes detailed instructions about construction, loading the vessel, and protecting it from water.
Bitumen is also relevant to comparisons with Genesis, where Noah is told to coat the Ark with pitch inside and out. The two accounts are not identical, but their waterproofing details belong to a broader Mesopotamian flood-story tradition. “Bitumen” is sometimes loosely translated as pitch, tar, or asphalt. Those terms overlap in practical use, but the ancient material was a sticky, water-resistant substance rather than modern industrial roofing tar.