She was dressed in a knee-length skirt and a short woolen blouse when she was buried in an earthen mound in southern Denmark. She was only a teenager when she died. Her small body was wrapped in a blanket and placed in an ox hide-lined coffin made of oak. Beside her, tucked within a small cloth sack, were the cremated remains of a six-year-old child. Now, over 3,000 years later, scientists are able to trace the young girl's journey across an ancient landscape.

They call her Egtved Girl, after the small town in Denmark where her body was discovered back in 1921. Today, through the analysis of strontium isotopes recovered from the girl's teeth, hair, nails, and clothing, researchers Karin Frei, from the National Museum of Denmark, and Kristian Kristiansen, from the University of Gothenburg, are able to determine where the girl originated and the area she travelled in the years leading up to her death.

Strontium is an element that exists in the earth's crust and is taken up by humans through the water they drink and the foods they eat. Since the isotopic signatures of strontium correspond to geographic location, scientists are able to determine where humans have lived, based on signatures found within the human body.

"I have analyzed the strontium isotopic signatures of the enamel from one of the Egtved Girl's first molars, which was fully formed when she was three or four years old, and the analysis tells us that she was born and lived her first years in a region that is geologically older than and different from the peninsula of Jutland in Denmark," says Karin Frei.

To pinpoint the girl's place of birth, Frei combined strontium signatures from her teeth with those found in her clothing. What the signatures indicate is that Egtved Girl was born in the Black Forest of South West Germany, almost 500 miles from where she died.

Not only did they identify where the girl was born, they were also able to track her final years of life before she was laid to rest in Denmark.

"If we consider the last two years of the girl's life, we can see that, 13 to 15 months before her death, she stayed in a place with a strontium isotope signature very similar to the one that characterizes the area where she was born. Then she moved to an area that may well have been Jutland. After a period of about 9 to 10 months there, she went back to the region she originally came from and stayed there for four to six months before she travelled to her final resting place, Egtved."

Frei continues. "Neither her hair nor her thumb nail contains a strontium isotopic signatures which indicates that she returned to Scandinavia until very shortly before she died. As an area's strontium isotopic signature is only detectable in human hair and nails after a month, she must have come to "Denmark" and "Egtved" about a month before she passed away."

Frei and Kristiansen's analyses reveal the girl's long journey leading up to her death. This marks the first time researchers have so accurately traced a prehistoric person's movements. And what this means for future archaeological research may include a clearer understanding of human migration in the past.