Huckleberry Finn is set during the middle of the 19th century, before the Civil War. Much of the story takes place in the fictional town of St. Petersburg, Missouri, on the banks of the Mississippi River.
Additional references are made to New Orleans and St. Louis, and many of the other picturesque towns which dotted the landscape along the Mississippi.
Mark Twain grew up in Hannibal, Missouri, and the town was the basis for St. Petersburg. He worked for a while as a riverboat pilot on the Mississippi.