Sorry. No over night parking at this Wal-Mart anymore here in Ontario, Oregon. A while back there was some questionable characters camping out and causing a security concern. Unfortunately, it ruined it for overnight parking for the good customers. There is RV parking availability for a small fee off of Exit 3 on Hwy 95 at the Chevron with outlets and shady trees in RV parking area.
Not supposed to, but people do. Worst case scenario, you may be woke with a knock from Ontario's finest and asked to move on.
People have yes in the far back of the parking lot next to the gas station
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