Alexandra P. was 19 when she disappeared in May 1987. Her body was found near her parents' house a few days later and police said they believed she had been sexually assaulted before her killing.
Despite investigating 2,000 people who they believed could have killed her, police came up empty.
But officials said forensic experts used the latest DNA analysis techniques to connect the murder with certainty to a man who was 28-years-old in 1987.
By 1988, the man had been convicted of killing three prostitutes in Kiel and a 19-year-old intern. He died in prison in 2004.