Named after the Rock River which runs through northwest Sioux County in Iowa, in the summer of 1897, the town of Rock Valley was platted by area landowner Col. A.J. Warren and the Chicago - Milwaukee Railroad. Thanks to the vision and planning of Col. Warren more that a century ago, Rock Valley residents today enjoy beautiful, wide tree-lined streets. Rock Valley has been and still is an aggressive, developing community actively seeking new growth while holding on to its traditional values and friendliness.