Over one hundred sites for water-powered mills were along the banks of Conococheague Creek and its tributaries in Franklin County, Pennsylvania and Washington County, Maryland. This book tells the stories of those mills -- from the colonial ones that began villages and roads, to those in milling's nineteenth-century heyday, to those seeing diminishing demand in the twentieth century. Nearly eighty Conococheague grist mills, as well as many sawmills, woolen mills, and paper mills are discussed herein. This book maps their locations, discusses their changing ownership and evolving technologies, and explains their rise and fall.