Yolo County is located in the northern part of the U.S. state of California. Woodland is the county seat. Yolo County remains a relatively rural agricultural area, home to the multi-billion dollar California tomato industry, which dominates 90% of the tomato market in the United States.
Yolo County was one of the original counties of California, created in 1850 at the time of statehood. The county has a total area of 1,023 mi², 99% of it is land and 1% of it is water. As of of 2000, there were 168,660 people, 59,375 households, and 37,465 families residing in the county.