Cedar Grove, Indiana  Cedar Grove is a town in Highland Township, Franklin County, Indiana, United States. The population was 156 at the 2010 census. Cedar Grove, originally known as Rochester, was platted in 1837 by John Ward. Ward built a large gristmill there. It was incorporated as a town in 1907. The Cedar Grove Bridge was listed on the National Register of Historic Places in 2014. Cedar Grove is located at (39.356407, -84.937034). According to the 2010 census, Cedar Grove has a total area of , all land. As of the census of 2010, there were 156 people, 75 households, and 47 families living in the town. The population density was . There were 84 housing units at an average density of . The racial makeup of the town was 98.7% White and 1.3% from two or more races. There were 75 households of which 25.3% had children under the age of 18 living with them, 44.0% were married couples living together, 16.0% had a female householder with no husband present, 2.7% had a male householder with no wife present, and 37.3% were non-families. 33.3% of all households were made up of individuals and 9.4% had someone living alone who was 65 years of age or older. The average household size was 2.08 and the average family size was 2.55. The median age in the town was 44.5 years. 19.2% of residents were under the age of 18; 7.7% were between the ages of 18 and 24; 23.7% were from 25 to 44; 35.2% were from 45 to 64; and 14.1% were 65 years of age or older. The gender makeup of the town was 47.4% male and 52.6% female. As of the census of 2000, there were 185 people, 75 households, and 54 families living in the town. The population density was 1,240.3 people per square mile (476.2/km²). There were 79 housing units at an average density of 529.7 per square mile (203.3/km²). The racial makeup of the town was 99.46% White, and 0.54% from two or more races. There were 75 households out of which 30.7% had children under the age of 18 living with them, 50.7% were married couples living together, 17.3% had a female householder with no husband present, and 28.0% were non-families. 26.7% of all households were made up of individuals and 12.0% had someone living alone who was 65 years of age or older.