Benton is third in a series covering Washington’s 39 counties, including how they got their names. In southcentral Washington where the Columbia, Snake, and Yakima rivers converge, sits Benton County. Benton covers 1,738 square miles, designating it as Washington’s 21st largest county. Although it’s not particularly big, it’s population is 186,486 people, giving it a density of 103 people per square mile. This is slightly higher than the state average of 101.2, and is the 9th highest among Washington’s counties….