The value of all land for sale in Adams County recently was $19 million, representing a combined 685 acres of land for sale in Adams County. Adams County ranks 35th out of 39 counties in Washington for the combined amount of land currently advertised for sale. Othello featured the most land for sale. Adams County has a large agricultural economy, with 713 farms recorded in the county during the latest U.S. Census. Farming activities in Adams County generate annual revenues of $24 million, most of which is from crops. Adams County is the 17th biggest county (1,929 square miles) in Washington. It's located in the Eastern Washington region of Washington.