SPOILERS - The next paragraph contains information relevant to the story. Specifically, the ending.
The Crimson King once conspired to topple the Tower and bring an end to all existence, but his plan was thwarted by Roland Deschain and Patrick Danville. The interior of the Tower is infinitely larger than its exterior, including a spiral staircase that passes rooms, each of which contains a scene from Roland's life. The uppermost door bears the inscription ROLAND, and passing through that door leads the gunslinger ever back into his own past during his flight across the Mohaine Desert to repeat the cycle of his quest once more.
- The Dark Tower
- Insomnia (A young Patrick Danville draws a picture with crayons of Roland Deschain standing in rose field of the Dark Tower).
- Low Men In Yellow Coats (the first part of King's novel Hearts in Atlantis).
- The Breathing Method (there are hints that The Club is located itself in the Dark Tower).
- The Little Sisters of Eluria (Prequel to The Dark Tower I - The Gunslinger). The Tower itself is not a part of the story. This story focuses on Roland trying to pick up Walter's trail. The Little Sisters have a red rose embroidered on their habits over their hearts.
- Ur - Although the Tower is not directly a part of the story, a picture of it appears on Wesley's Kindle and the low men in yellow coats make an appearance at the end of the story in which they reference both the tower and the rose.