For more than 30 years, Prince William County police did not know the identity of the person whose bones were discovered at the foot of Bull Run Mountain.
The remains were found in 1982 by a hiker in a wooded area of Haymarket.
In 2001, a DNA sample from the remains were entered into a national database. But the sample sat unmatched for another decade until the family of a long-missing Takoma Park girl submitted their own DNA samples in connection with another missing persons case.
It was May 10, 2012, before crime analysts got a match. The victim was identified as Cynthia Joan Gastelle, the 18-year-old Takoma Park girl who had disappeared in 1980.
Police at the time announced her death as a homicide, although they have not said how she was killed. Detectives continue to seek information that could lead to her killer.
Police were also asking for help finding the victim's then-boyfriend, possibly named "Mike," and released a photo of the man. Police said he was not a suspect in the case.
Gastelle, who would be 50 years old now, was originally reported missing April 3, 1980, police said.
She was 5 feet tall, weighed 90 pounds, and had brown hair and brown eyes.
Anyone with information can anonymously call 1-866-411-TIPS (8477).