What purchase increased the interest for exploration west?

The Louisiana Purchase in 1803 significantly increased interest in westward exploration. This acquisition, which doubled the size of the United States, provided vast territories ripe for exploration and settlement. It spurred expeditions, most notably the Lewis and Clark Expedition, aimed at mapping the new lands and establishing routes for trade and expansion. The purchase not only fueled the desire for exploration but also heightened the nation's ambition for growth and manifest destiny.