Samuel Clemens chose his pen name based on his love for river life. What was the river that he lived by as a young boy ?

Samuel Clemens was born in Missouri, and he grew up in the town of Hannibal on the Mississippi River. He got a job on one of the many steamboats that plied the river during the antebellum period, and his pen name, Mark Twain, a call that steamboat crews would use while taking depth soundings in the river. He moved West for a time, and many of his early works are set in the frontier, but his most enduring work, The Adventures of Huckleberry Finn, published after he had moved to the east, is set literally on the Mississippi River. While Twain never spent that much time on the river as a steamboat apprentice pilot (the Civil War essentially choked off steamboat traffic for a time) he memorably evokes the culture and the dialect of the people who lived on the river, including the many enslaved African-Americans who lived along its shores.