Marguerit Lehmkuhl had to be flown by medical chopper to a nearby hospital after someone spotted the vehicle and alerted police Sunday afternoon.
It was a startling but welcome discovery, given the concern of her loved ones -- as well as the authorities.
Police say most dementia patients are found within 20 minutes to 24 or so hours.
The search for Lehnkuhl had entered its fourth day when Clifton police got a call from their Southern counterparts.
Authorities were able to identify her thanks to a Silver Alert that included the make, model and license plate number of her car.
Lehmkuhl -- who has dementia and must take several medications each day for other conditions -- had driven nearly 500 miles in her 2006 Chrysler 300 after her family said her car vanished from her driveway before noon Thursday, authorities said.
She has no connection to the area where she was found, they said.
She apparently just kept driving -- even stopping to refill her gas tank. Family members said she hadn't eaten in days, however.
A HealthNet Aeromedical Services chopper flew her to Preston Memorial Hospital, where Lehmkuhl was in stable condition, authorities said.
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