The Adventures of Huckleberry Finn begins in the town of St. Petersburg, Missouri, which based on Twain's childhood home in Hannibal, Missouri, in roughly the 1840s. Huck stages his own death to escape his cruel, alcoholic father and runs away to nearby Jackson Island on the Mississippi, where he encounters the escaped slave Jim.
The setting quickly moves to the Mississippi River as Huck and Jim head north on a raft so that Jim can find freedom. The two, however, have many adventures on the shore as they pass through such states as Kentucky, Illinois, and Arkansas. Twain famously contrasts the innocence, freedom, bounty, and beauty of nature as Huck and Jim experience it on the Mississippi with the ignorance, greed, poverty, and corruption of human civilization as the two experience it on shore. The onshore settings vary from the harsh, dry, cruel poverty of Arkansas towns to the wealth and "culture" of the Shepherdson planation, where, ironically, the Shepherdsons, who perceive themselves as gentle and refined, own slaves and engage in a bloody feud with the Grangerfords.
The story ends in Arkansas, where Jim finds out, after a series of adventures orchestrated by Tom Sawyer, that he is free, and Huck decides to head out west to find freedom from civilization.