"Outside Skamania, Washington is the 848 foot-tall Beacon Rock that overlooks a breathtaking section of the mighty Columbia River. The core of an ancient volcano, Beacon Rock is essentially a basalt plug; the Missoula Flood waters eroded away the softer outer material. Captain Clark wrote in his journals, '…a remarkable high rock on Stard. Side about 800 feet high & 400 yds round…' His estimates were exceptionally close.