Kellie Ann Carmichael vanished 23 years ago. Her body was just found in the Blue Mountains.

In 2001, Kellie Ann Carmichael vanished after checking out of a backpackers' hostel in NSW's Blue Mountains.

The young woman was just 24 years old, and had travelled to Katoomba from her home in the Victorian city of Geelong. ABC reports that she was there to seek her friends' help with her diagnosed schizophrenia.

She went missing on April 29, 2001, and was never seen again, in a cold case that baffled investigators for years. 

Carmichael's remains were found nearly exactly 23 years later, on April 30, 2024.

Image: Australian Missing Persons Register.

Police discovered Carmichael's remains in bushland near Katoomba during an unrelated police operation, where officers were abseiling down a cliff.

"The human remains initially located and seized have now been formally identified as those of missing person Kellie Ann Carmichael, and her family have now been notified," police said.

Personal items Ms Carmichael took with her to the area had previously been found, but human remains had not been located until now. On the day of her disappearance, Carmichael had left most of her belongings at the hostel, telling the staff that she was going for a walk.

When her parents hadn't heard from her in five days, they were shocked to call the hostel and find that her personal ID, wallet, phone, camera, toiletries and cards had not been picked up at reception.

Much media speculation ensued, with some theorising her disappearance was the work of a serial killer.

Image: Australian Missing Persons Register.

Police initially probed the possibility she took her own life, in part because she was suffering from schizophrenia, with the homicide squad first launching an investigation in 2004. The family maintained she was a victim of murder.

In 2011, a $200,000 reward was issued for information related to the case after a 2009 coronial inquest ruled Ms Carmichael had died but was unable to shed light on a cause or circumstances.

Ms Carmichael's parents Margaret and John have previously said they felt robbed by their daughter's mysterious disappearance.

"We've never had the chance to have our daughter... our family has never been the same," Mrs Carmichael said in 2011.

She was found in an unrelated police operation in the Blue Mountains. Image: Getty.

The police minister in 2011, Michael Daly, said, "Please give her family the closure that they deserve. Please come forward with information.

“And understand that if you have been responsible for doing harm to Kellie Ann, the police will never close this file.

“They will hunt you until the day you die.”

An investigation is being conducted by the Unsolved Homicide Team and a brief of evidence being prepared for the coroner.

Following the discovery of Kellie Ann's body, the site was searched, and further remains were found there in May, according to ABC and NewsCorp reports.

-With AAP