The fictional town where the first part of Adventures of Huckleberry Finn takes place is St. Petersburg. Mark Twain places Huck at home in this Missouri town at the beginning of the novel, after the events of The Adventures of Tom Sawyer. The Widow Douglas and Miss Watson are caring for him, while Huck struggles with the demands of respectable society and his desire for freedom.
St. Petersburg is fictional, but it is widely understood to be modeled on Hannibal, Missouri, where Twain grew up along the Mississippi River. That real setting helped shape the novel’s detailed portrait of river towns, steamboats, local characters, and small-town life.
A common mix-up is Cairo, which Huck and Jim hope to reach as they travel south on the Mississippi. Cairo is an important destination in the plot, but it is not the opening town. The journey later continues toward New Orleans, while St. Petersburg remains Huck’s home base.