The Adventures of Tom Sawyer (1876). I am wholly aware that I am committing some form of literary heresy with that statement. The latter is widely viewed as a children's story, but it contains more truth about the struggle to be an adventuresome boy while still growing into a man. It deals with young (and honest) love, financial inequities, and life on what was essentially the frontier.
In contrast, Huck Finn abandons its deeper truths after the first third of the story, first in favor of a comical take on Americana con-artistry, then in destroying the virtue built into the Tom Sawyer character nine years earlier. Maybe it was how disrespectful Twain was to his own creation that soured me most on this book, but I think it also had something to do with the easy realization that there is no adequate ending to the tale. Instead, Twain places Jim back in shackles and cannot seem to return Huck to the realization that a slave is also a person and should be respected as one.
If the second half of Huck Finn had been as well written as the first half (or the first third, especially), it would be the American masterpiece it is celebrated to be. Instead, the book gets bogged down with the idea that young women (especially) are creatures to be marveled at (and perhaps politely lusted after), that men are essentially creatures looking to take advantage of others, and that the injustice in slavery is largely based in the separation of families – a huge step back from the early revelations at which Huck grasps to understand.
The absolute worst part of the story is the handling of the revelation of what happened to Huck's father (even worse than Tom's appearance). It feels cheap, and it is quite obviously a cheat. As a frustrated writer, I know the temptation to wrap up unattended – and sometimes forgotten – elements with a wave of the hand and a simple statement that voids any concern for them. I was hoping for something much better from a book as well regarded as this one is.
Now, all of this is not to say that I am not happy that I read the book. There is enough good material to make the less than good sufferable. But it doesn't end up being the story it starts out to be (yes, I have been insanely guilty of that myself) and seems to wander away from having a point or even a consistent point of view.