Final answer:
The two main goals of the Lewis and Clark expedition were to explore and map the Louisiana Purchase territory and to seek a Northwest Passage, a continuous water route from the Mississippi to the Pacific Ocean.
Step-by-step explanation:
Main Goals of the Lewis and Clark Expedition
The primary goals of the Lewis and Clark expedition, led by Meriwether Lewis and William Clark from 1804 to 1806, were to explore and map the new territory acquired by the United States in the Louisiana Purchase and to find a continuous water route from the Mississippi to the Pacific. President Thomas Jefferson had tasked them with identifying potential trade routes, especially a Northwest Passage, and to survey the land for geographical information. Additionally, they were to document the natural resources, plant life, animal species, and establish relationships with native tribes, fostering future trade and claiming U.S. sovereignty over the region.
Despite the hope for discovering a navigable waterway to the Pacific, this goal was not achieved because such a passage does not exist. However, they successfully mapped the territory and greatly contributed to the understanding of the geography west of the Mississippi, as well as solidified the United States' claim to the vast new land.