Cross Plains, IndianaCross Plains is an unincorporated community in Brown Township, Ripley County, in the U.S. state of Indiana.HistoryCross Plains was founded in 1826 and was named for the fact two roads meet at the town site. A post office has been in operation at Cross Plains since 1826.DemographicsThe United States Census Bureau delineated Cross Plains as a census designated place in the 2022 American Community Survey.