The combined value of land and rural real estate for sale in Custer County, Idaho, recently on Land.com was around $111 million. This represents around 4,000 acres of farms, ranches, and rural real estate for sale in Custer County. Custer County ranks 32nd out of 44 counties in the Gem State for the total number of acres of land currently advertised for sale. Mackay featured the most land for sale. Economically speaking, Custer County's is largely dependent on mining and mineral extraction-related businesses and services. Custer County is one of the ten largest counties in Idaho (4,938 square miles). It's located in the Central Idaho region of the state.