At the Riffe Lake overlook is an interpretive marker that tells the story of how Mossyrock Dam’s construction in 1968 flooded the last remnants of Riffe and Kosmos, which were located where Riffe Lake is now. The Riffe original town center marks the former town center.
Prior to construction of the dam, the valley featured farms that alternated with patches of second-growth timber and cutover lands, brilliant with flaming maple, fox glove, and fireweed. Some of the denuded hills already showed the deep gullies of erosion. Here and there were unpainted shacks of clapboard, the families of loggers employed in the near-by logging camps and mills lived. In the more fertile parts of the bottoms were well-cultivated farms, dating back to the late 1800s, with broad fields of grain and clover, meadow lands of timothy and redtop, and occasional orchards.