Inga Maria Hauser was last seen alive on 6 April 1988 as she journeyed by ferry from Scotland to Northern Ireland.
The 18-year-old’s body was found dumped in a remote part of Ballypatrick Forest on the outskirts of Ballycastle, Co Antrim, a fortnight later.
Officers from the Police Service of Northern Ireland (PSNI) yesterday held a briefing at Cairnryan ferry terminal in Stranraer where they appealed for information about the teenager’s movements in Scotland.
Prior to her death, the German backpacker travelled around England, from London to Bath and on to Liverpool. From Liverpool she journeyed to Preston and then north to Inverness, before taking the train to Glasgow and on to Stranraer.
Police believe a number of people may have been involved either directly or in the cover-up of the murder.
Police have a male DNA profile from the crime scene but have yet to secure a positive match. Detective Chief Superintendent Raymond Murray said: “We are investigators and we keep an open mind but the evidence and the information and the intelligence that we have to date has led us to focus on a very, very small number of individuals.”
Mr Murray confirmed that all the suspects are still alive, though he declined to confirm whether they still live in the north Antrim area.
“They will know who they are,” he said.
He added: “I think there are people out in the community who know exactly what happened, I think there are one or two who were possibly involved in the aftermath of this killing. I think at least one of them is finding it very difficult to live with.
“We are all getting older, we are moving on – is this something that you want to take with you to your grave?
“It is not too late now to examine your own conscience and come forward to the police.”
“What we need is just those few fractional pieces of evidence to help us complete the picture. We think we are close.”
The detective also revealed Ms Hauser’s poignant last entry in her diary.
He said: “Her last notebook entry on 6 April reads: ‘Went from Glasgow to Ayr and from there to Stranraer to get over to Ireland.
“‘Saw the sea. Beautiful and mysterious. Wonder where I stay tonight. Need more money.’
“Sadly, Inga’s final resting place in Northern Ireland was in Ballypatrick Forest,” he said.