From the case of the "body in the bog" to the "woman in the well", some of the investigations date back decades.

It is a part of Interpol's Identify Me initiative to appeal to the public for help regarding the bodies that were discovered as far back as 1976 across Belgium, France, Germany, Italy, the Netherlands and Spain.

Despite extensive police efforts so far, these women have not yet been identified.

"We want to identify the deceased women, bring answers to families, and deliver justice to the victims," Interpol secretary general Jurgen Stock said in a statement.

"We can't do it alone," he added.

The operation expands on the initiative, first launched in 2023, when Interpol sought to shed light on the names and fates of 22 women.

That effort yielded 1,800 tips from the public, including information that led to the identification of British woman Rita Roberts' remains through her flower tattoo.

Ms Roberts was 31 when she left Cardiff in February 1992. She last made contact with her relatives in May that year, and her unidentified body was discovered in Antwerp a month later.

An investigation determined that she was a victim of murder.

Within two days of the launch of the first phase of Identify Me in 2013, relatives of Ms Roberts contacted the appeal hotline after they recognized their relative's tattoo from news coverage.

Interpol said the case "remains part of the international effort to request information, identify and seek justice for these deceased women".

The body in the forest

On 2 June 1997 the naked body of a woman, thought to be aged between 18 and 22 years old, was discovered along a forest path in Altena-Bergfeld, Germany.

Interpol said she had been raped, strangled and then set on fire.

However, the location where the body was found is not where the crime was committed, authorities said.

The woman was found with a tooth gem on, but Interpol found little other stand-out characteristics that could help identify her.

The woman with the artificial nails

Discovered on 31 May 2009 in the Albert Canal in Vise, Belgium, and estimated to be between 14 and 24 years old, this woman died a violent death as well.

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She was killed, Interpol said, and her body was weighed down and remained underwater for between one and five weeks before she was found.

The woman had artificial nails and on both ring fingers they were decorated with a floral pattern.

The initial investigation revealed that the young woman had been living in the Benelux region for several years after a childhood in eastern Europe.

These are just two of the 46 cold cases that Interpol are hoping to solve.

Click here to view them all.