@Devenox: Stephen King has a reputation for writing horror books, and for good reason. "The Dark Tower" though, isn't so much horror. In fact, it's hard to say exactly what genre it fits into. The closest I can come up with would be sci-fi, but even that isn't too accurate.
Without giving away any spoilers, the Dark Tower is, essentially, about a gunslinger named Roland in a Camelot-wasteland world that has "moved on" from its days of glory. Roland's quest is to reach the Dark Tower, which stands at the center of everything, the hub of the universe and a structure keeping existence in existence, in order to keep a figure known as the Crimson King from destroying it and ending all existence. Through his travels, Roland journeys back and forth between his world and ours, to the 1960s, the 1980s, and the present day. From each time period, he ends up bringing along a companion, willingly or unwillingly: a coke junkie and drug runner from the 80s, a legless and viciously schizophrenic Black women from the 60s, and a 12 year old rich boy from the present day who might as well be orphaned.
King started writing the DT in the late 70s, originally as a short story, and then shelved it for 20 years. After he was hit by a van in Maine and almost died in 2000, he took to the DT again and finished the series by 2006 or so. King's described the DT series as his "magnum opus", his life's work. You can find evidence of this in that he ties some elements, characters, and even fragments of the DT storyline into his other works (Insomnia, for example). Because after all, the Dark Tower stands at the center of everything.
