Museo del Origen is the island's most useful stop, especially if you have heard Mexcaltitán described as a possible Aztlán. Its exhibits use local finds, images, and stories to explain the Mexica migration tradition and the arguments around the island's place in that story.
It is small, but it gives the visit a frame. See it before wandering the lanes, and the village feels less like a curiosity and more like a place with a stubborn myth attached to it.