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This is the sunset from "Spoil tip" we call "Zuri yama" in Shimizusawa Yubari. Yubari is the town which prospered as the coal mine once. This coal mine was already closed. Even if many facilities disappeared, but this mountain continues leaving the memory of a coal mine. This corridor is a work of Mr. Shunsuke Watanabe of the Yubari Shimizusawa Art Project.