From Jennifer Beard to Marie Jamieson, unsolved murders can linger in the public consciousness for years - and police never give up hope that fresh leads will turn up the killer.
Welsh hitchhiker Jennifer Mary Beard's body was found under the Haast River bridge on January 19, 1970 - 19 days after her murder.
Her green shorts were rolled down below her knees and a red bra top had been pushed up near her neck. The body was so badly decomposed that pathologists were unable to establish a cause of death.
Miss Beard, who was teaching in Tasmania, was touring the South Island and had arranged to meet her boyfriend, Reg Williams, at Milford Sound in early January. He raised the alarm when she failed to arrive.
Police interviewed more than 50,000 people and began tracing the owners of 35,000 Vauxhall cars throughout New Zealand. Although a prime suspect was identified, he was never charged.
In a number of other unsolved murder cases, women disappeared after accepting rides from motorists or being dragged into cars.
On January 30, 1976, the strangled body of 13-year-old Tracey Ann Patient was found in the Waitakere Ranges, the morning after she disappeared while walking home in Henderson. A leading theory was that she was abducted.
Her distraught family returned to England to live in near-seclusion.
There was no such thing as DNA testing in those days, and the head of the inquiry, Detective Inspector Bruce Scott, would later say: "Some inquiries you get all the breaks. We never got any ... "
Twenty years later, there was renewed interest in Tracey's disappearance when police re-examined the unsolved murders of two Bay of Plenty teenagers in the 1970s.
Olive Walker, 18, was brutally murdered and her body dumped at a rest area south of Rotorua in 1970.
Mona Blades, 18, disappeared while hitchhiking from Hamilton to Hastings on Queen's Birthday Weekend in 1975.
In 1996, police used "modern methods" to investigate the possibility that all three young women fell prey to a serial killer. But the inquiry drew a blank.
Ashburton 15-year-old Kirsty Bentley disappeared on New Year's Eve 1998 near the Ashburton River bridge. Her underpants and boxer shorts were found on the riverbank. Her body was later discovered in the Rakaia Gorge, 55km northeast of Ashburton.
Police in Auckland remain hopeful that scientific advances or fresh leads will help resolve several murders where inquiries have been scaled down. These include:
* The 1995 killing of Parnell recluse Elizabeth Marusich, whose decomposed body was found in the Domain.
* Herne Bay woman Claire Hills, abducted and burned to death in her car on Mangere Mountain in April 1998. Police have been close to an arrest on several occasions.
* Japanese tourist Kayo Matsuzawa, whose decaying corpse was found inside a cupboard in the Centrecourt building in downtown Auckland.
* Marie Jamieson, who disappeared while walking along New North Rd, Kingsland, on February 10 last year. Her naked body was found nine days later behind an engineering workshop in Ranui, West Auckland.
Last month, after a suspect's relative admitted lying to protecthim, Wellington police reactivated inquiries into the Wellington Trades Hall bombing that killed caretaker Ernie Abbott in 1984.