Not one for small gestures, businessman Sam Hill built a full-scale replica of Salisbury Plain's Stonehenge on the cliffs above the Columbia River. Dedicated as a peace memorial to Klickitat County's soldiers killed in WWI, his Stonehenge was built of poured concrete and represents an intact site (unlike its tumbled-down English cousin).
Hill planned that his Stonehenge would line up for celestial events such as equinoxes. It's popular for odd rites and ceremonies, and offers great views of the gorge.