History:

Prosser is easily identified as the historic hub of Benton County. Since its first homestead in 1882 by Colonel William Prosser, an agent for the Department of the Interior, the land along the Yakima River has provided for rich, fertile ground for this agricultural community. Prosser's history is flavored by Native Indians who hunted and fished in the area. Wild mustangs accented its landscape. E.F. Benson, Chief Examiner for the Northern Pacific Railroad built the power house on the river and established the Prosser Falls Land and Irrigation Company. The Benton County Court House has preserved much of its original architecture. It was designated as the first building in Benton County to be marked an historical landmark in 1976.