“The Rime of the Ancient Mariner” by Samuel Coleridge is “strange” in at least two respects.
Primarily, there is something unusual in the way in which the Mariner gets the attention of the man listening to the story. The listener is on his way to a wedding, to which he has been invited as a guest. At first he tries to get away from the Mariner, but he becomes “hypnotized” by the glittering in the eye of the latter. So he stays and listens, mesmerized almost against his will.
In another respect, the tale itself is strange. The Albatross represents the start of the supernatural events occurring on the Mariner’s ship. First, it brings good fortune, even after it is shot. Subsequently, it is strange when all the crew except the Mariner himself die. They then supernaturally return to the ship, after which it sails so fast that the Mariner goes into a trance. The culmination of all this is that the Mariner seeks someone to hear his confession.
The central strangeness of the poem is therefore the supernatural element, both in the way the narrator tells his story, and in the story itself.