In 1803, the Louisiana Purchase sparked interest in expansion to the west coast. The USA purchased 2,100,000 square km of largely unknown territory from France for 3 cents per acre. This huge swath of land stretching from New Orleans to Canada now about forms about 23% of the USA. President Jefferson sent Lewis and Clark to study the Indian tribes, botany, geology, Western terrain and wildlife. The journal details their trek from the Missouri River to the northern Pacific coast and back.