"The Willows" by Algernon Blackwood is a novella published in 1907. Two friends on a canoe trip down the Danube land on an isolated island where they encounter mysterious supernatural forces emerging from the surrounding wilderness. As strange shapes rise from the willow trees and inexplicable phenomena intensify, the men realize they may have crossed into another dimension—a hostile realm where unseen entities demand sacrifice. H.P. Lovecraft called it the finest supernatural tale in English literature. (This is an automatically generated summary.)
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