Among the state's most distinctive geologic features are the chalk monoliths of Gove County. Sculpted by erosion, these formations are part of the Smoky Hill Chalk Member of the Niobrara Chalk. Erosion continues to wear away pieces of these monuments, as was demonstrated by the dramatic toppling of Cobra Rock in 1998 and the collapse of Castle Rock's tallest spire following a thunderstorm in July 2001. more…