Neat, Convenient, Busy
Hilgard Junction is a small, Riverside day use area, travel rest-stop and campground at the junction of I-84 and Highway 244 on the Grande Ronde river at the base of Mt. Emily.
This park is near La Grande, Oregon so if you are not just resting on your trip, you can run into a cute little university town to explore the Eastern Oregon local life.
Crystal clear water runs this high in the Grande Ronde, making for fun swimming and water play. Make sure to bring your gold pan to this shallow river bed, as it has been historically found all along this river. The RV park has no connections so bring your generator and solar panels with you. This is self contained type of camp, that provides two bathrooms and firewood.
It is an ADA friendly area with paved rv spots and designated well kept tent spots. Keep in mind this park is directly off of the interstate so there are a lot of random travelers coming and going at all hours of the day and night. One minor bit of awkwardness is that there is a youth correctional facility less than a mile up the road. So your traveling children maybe curious and ask odd questions if they see it.