The Walla Walla County Courthouse is located at 315 West Main Street, Walla Walla, WA 99362; phone: 509-524-2780.
Native Americans (Umatilla, Walla Walla, and Cayuse Tribes) were the first people in recorded history to live in Walla Walla County. Lewis and Clark explored the area between 1804 and 1806. Missionary settlements were established around 1836. The City of Walla Walla was settled in 1859 and became the County Seat on November 7, 1859. The County and its cities contain numerous historic and cultural resources that reflect the unique heritage of this area.