Lines 25-30 describe the power of the waters of the river that flows through Xanadu. While the opening lines of the poem celebrate Xanadu as a human creation, this passage celebrate the creations of nature. The water is associated with different semantic areas: words like "wood" and "dale" convey an idea of fertility while "caverns", "measureless" and "tumult" suggest the power of water to erode the land. The river flows for five miles before reaching the caves and merging into the ocean in tumult. Note the strong alliteration of S and R in lines 26-28. The noise of the river falling into the ocean introduces a dream-like sequence where Kubla Khan hears ancestral voices that warn of an impending war.
Lines 31-36 continue the dream-like atmosphere, although combining it with precise details and thus creating a series of paradoxes. These climax in line 36 where the pleasure dome is described as both sunny and containing caves of ice. Those critcs who read the poem as a metaphor for literary creation support their reading with these lines. They claim that the pleasure dome is "a miracle of rare device", a description that is fitting for a work of art too. In addition, they take the fusion of opposites in line 36 as representing the process of creating art.