"Everything has its wonders, even darkness and silence, and I learn, whatever state I may be in, therein to be content." - Helen Keller _ Into the darkness... _ Creeping through Wind Cave in South Dakota. This hidden world beneath the prairie is one of the longest and most complex cave systems in the world. _ Many of the walls are lined with a rare formation called "boxwork" - where mineral deposits form between softer rock and remain after the exterior is eroded. In fact 95 percent of the world's discovered boxwork formations are found in Wind Cave. _ Even though there are 140.47 miles (226.06 km) of explored passageways, 4 new miles of cave passages are being discovered each year. _ Settlers have been exploring the cave system since 1881. But the Lakota indigenous people knew of it as a sacred place, and the origin of their people when they emerged from beneath the ground eons ago. _ After exploring it myself I can see why. We live in an amazing world. _ #southdakota #DoBigThings #visitrapidcity

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