Workmen discovered Miss Hall's remains in undergrowth on Monday
The disappearance of hospital worker Melanie Hall, whose remains have been found in a bag next to the M5, prompted a major missing persons inquiry.
Detectives began their investigation after the 25-year-old disappeared from Cadillacs nightclub in Bath on 9 June 1996.
Despite a £10,000 reward offered for information and a reconstruction on the BBC's Crimewatch programme, no trace of the hospital clerical worker was ever found.
The last sighting was of Miss Hall sitting on a stool on the edge of the dance floor at Cadillacs at 0110 BST.
Officers always said the case was still open and had carried out extensive searches of the River Avon several times since 1996.
There were several leads, the last major one in 2003, when a search was centred on a field used by motorcyclists, near Inglesbatch, on the edge of the city.
A mound of earth on the site was searched to no avail.
An inquest requested by her parents, Steve and Pat Hall, in November 2004 recorded an open verdict.
Because no body had been found the coroner had to get special Home Office permission to hold the hearing.
The bones were found at the side of a slip road off the M5 on Monday
Avon Coroner Paul Forrest said there was no explanation for Miss Hall's disappearance but speculated she had been killed soon after she went missing.
He said circumstances surrounding the case suggested she was unlawfully killed but a lack of evidence forced him to record an open verdict.
In 2006 her parents used the 10th anniversary of Miss Hall's disappearance to make a fresh appeal for information.
Speaking at the time Mrs Hall said: "We feel somehow that we're running out of time - we would just like an outcome."
But now, a set of bones found alongside the M5 have been revealed to be those of the missing Bath hospital worker.
The discovery was made by a worker clearing away overgrowth which had not been cut back for 10 years.