Final answer:
The last glaciers in the Great Lakes region melted away around 12,000 years ago, marking the end of the last ice age.
Step-by-step explanation:
The last glaciers in the Great Lakes region melted away about 12,000 years ago, signaling the end of the last ice age. Multiple sources substantiate this timeline, including geological studies and documented climate changes. The massive ice sheets that once covered parts of the northern United States and Canada retreated, leaving behind a transformed landscape that included features such as Cape Cod and the Great Lakes themselves.