Seneca Rocks

Seneca Rocks in Pendleton County, WV The rock is composed of fine grains of sand that were laid down approximately 440 million years ago, in an extensive sheet at the edge of ancient ocean. Years of geologic activity followed, as the ocean was slowly destroyed, and the underlying rock uplifted and folded. Millions of years of erosion stripped away the overlaying rock and left remnants of the arching folds in formations such as Seneca Rocks.