The town of Rock Valley was platted in 1879 by a Colonel Warren, a Civil War veteran, and the Chicago Milwaukee & St. Paul Railway on ground owned by Warren. https://www.cityofrockvalley.com/site/history.html
Geography
Rock Valley is located at . According to the United States Census Bureau, the city has a total area of, of which is land and is water. Rock Valley is located on U.S. Route 18.
As of the census of 2010, there were 3,354 people, 1,283 households, and 870 families living in the city. The population density was. There were 1,356 housing units at an average density of. The racial makeup of the city was 92.2% White, 0.3% African American, 0.4% Asian, 5.8% from other races, and 1.2% from two or more races. Hispanic or Latino of any race were 12.2% of the population. There were 1,283 households of which 32.9% had children under the age of 18 living with them, 60.9% were married couples living together, 4.2% had a female householder with no husband present, 2.7% had a male householder with no wife present, and 32.2% were non-families. 28.8% of all households were made up of individuals and 13.5% had someone living alone who was 65 years of age or older. The average household size was 2.54 and the average family size was 3.16. The median age in the city was 35.8 years. 27.3% of residents were under the age of 18; 8.1% were between the ages of 18 and 24; 25.3% were from 25 to 44; 19.4% were from 45 to 64; and 19.9% were 65 years of age or older. The gender makeup of the city was 49.4% male and 50.6% female.
2000 census
As of the census of 2000, there were 2,702 people, 1,124 households, and 750 families living in the city. The population density was 1,599.9 people per square mile. There were 1,202 housing units at an average density of 711.7 per square mile. The racial makeup of the city was 98.48% White, 0.11% African American, 0.07% Native American, 0.33% Asian, 0.59% from other races, and 0.41% from two or more races. Hispanic or Latino of any race were 1.04% of the population. There were 1,124 households out of which 29.4% had children under the age of 18 living with them, 59.8% were married couples living together, 5.2% had a female householder with no husband present, and 33.2% were non-families. 30.9% of all households were made up of individuals and 16.5% had someone living alone who was 65 years of age or older. The average household size was 2.38 and the average family size was 3.00. In the city, the population was spread out with 25.4% under the age of 18, 9.6% from 18 to 24, 24.4% from 25 to 44, 18.3% from 45 to 64, and 22.3% who were 65 years of age or older. The median age was 38 years. For every 100 females, there were 92.6 males. For every 100 females age 18 and over, there were 89.8 males. The median income for a household in the city was $36,967, and the median income for a family was $45,074. Males had a median income of $31,219 versus $20,833 for females. The per capita income for the city was $19,660. About 1.9% of families and 4.1% of the population were below the poverty line, including 6.7% of those under age 18 and 3.2% of those age 65 or over.
The Rivers Bend Campground first opened in late October 2009. It was given to the City of Rock Valley by Van Zee Enterprises. Previously used to mine sand and gravel, this former quarry was used to make the campground. The campground was constructed by the major efforts of RC Concrete, the City Crew and students from Northwest Iowa Community College.
The city of Rock Valley hosts a celebration, which is usually held during the first week of August. This typical features a tractor pull, car show, parade and other activities.
