Anne Marie Jeffery, 73, was camping with her husband and friends in northern NSW four years ago, when she went to use the public bathroom.
She has not been seen or heard from since.
It was about 9am on Tuesday 25 August 2020, when Anne walked between the Lake Arragan campground, and a public toilet.
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A wide scale search was launched when she could not be found, however, after three days there was still no sign of Anne.
Now, four years later, police have launched a fresh appeal for information into Anne’s disappearance.
Detective Inspector Ritchie Sim said he hoped the memories of those at the campground at the time would be triggered.
“Anne’s disappearance was sudden and devastating for her family, friends and the community,” he said.
“On all accounts, Anne was a wonderful person who enjoyed camping with her loved ones; making her disappearance all the more devastating.
“I hope this reappeal will trigger memories of those who were in the area when Anne Marie disappeared. The information you have may be the missing puzzle piece that helps detectives find Anne.”
Anne is described as of Caucasian appearance, with a slim build and grey hair. She was last seen wearing a red and pink top, woollen leggings, red shoes, and a beanie at the time she disappeared.
Anyone with information is urged to contact Crime Stoppers on 1800 333 000.