The second westward surge reached the: mississippi river, appalachian mountains, oregon territory

The answer is Mississippi river.

The Second Westward happened before the Revolutionary War. The Americans started crossing the Appalachian Mountains in order to get into the Ohio valley. The leader was Daniel Boone. He led his people to the Kentucky country and after the war the families settled the territory. The United States settled westward to the Mississippi River.

Mississippi River

Explanation:

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