There was a combined around $116 million of farms, rural land, hunting land and other land for sale in Hawaii's Honolulu County recently on Land.com. The total of all Honolulu County land for sale was approximately 100,000 acres. Based on the combined acreage of land and rural property for sale here, Honolulu County has the most land for sale of the five counties in Hawaii. Among cities in Honolulu County with farms and rural land for sale, Honolulu had the most land for sale. Honolulu County is one of the ten largest counties in Hawaii (2,166 square miles, or some 100 percent of the state's total land area). It's located in the Oahu Hawaii region of Hawaii.