The Louisiana Purchase had given America many, many rivers, streams, and passageways leading to the ocean that nobody had known about. We did have maps back then either. Jefferson had hired Lewis and Clark to travel America to find all of the secret passages and possibly make a map for everyine to use. This event was very important to America because as a result of Lewis and Clark's journey, we now have maps. Found on page 348 of the American History textbook written by McDougal Littell.