Flood narratives appear across disconnected cultures with striking consistency. The Sumerian account describes Utnapishtim, warned by the god Ea, who built an ark and survived a world-destroying deluge with his family and crew. Independently, Native American traditions speak of ancestors surviving in a great canoe. These aren't vague mythological echoes. They describe specific survival scenarios: vessels, advance warning, selective preservation of life. When geographically separated cultures preserve nearly identical catastrophe memories, the question becomes unavoidable. Are we looking at shared myth, or shared experience? The geological record confirms massive flooding events at the end of the last ice age. Meltwater pulses, glacial lake outbursts, and rapid sea level rise would have been catastrophic to coastal populations. If these stories encode real events, they may represent humanity's oldest disaster accounts, passed down through oral tradition for thousands of years.