From US 30, take a left at N. Sherman light (Light after N. Hills). Right on E. Philadelphia St. (light). Follow all the way through the city to Carlisle St. Must go left or right on Carlisle.
If you turn right, then turn left into the fairgrounds (light). The grandstand will be on your right. Recommended route.
If you turn left, get in the right lane and turn right onto W. Market St. Then turn right into the fairgrounds. More traffic.
I live off Oregon Pike and it takes around 45 minutes.
Charlie