PASSAU, Germany, July 16, 2008 -- Two Germans share the longest proven family tree in the world.
The men, Manfred Huchthausen, a 58-year-old teacher, and Uwe Lange, a 48-year-old surveyor, had known each other from living in the same village, about half a mile apart from each other.
But they never knew they were related through a 3,000-year-old shared ancestor.
They only recently found out they are both true descendants of Bronze Age cave-dwellers who lived in the area three millenniums ago.
Thanks to a DNA test on well-preserved Bronze Age bones found in the Lichtenstein cave in the foothills of the Harz Mountains in Germany's Lower Saxony, the men can now claim to have the longest family tree in the world.
"Before the discovery, I could trace my family back by name to 1550," Lange said. "Now, I can go back 120 generations."
Lange comes from the small village of Nienstedt, which is near the excavation site.
"We used to play there as kids," he told ABC News. "If I'd known that there were 3,000-year-old relatives buried there, I would not have set a foot in that cave."
A local team of archaeologists discovered the L. cave, which had been hidden from view, in 1980. But it wasn't until 1993 that they found the Bronze Age remains.
The cave was used between 1,000 and 700 B.C., according to archaeological investigations conducted by scientists at the nearby University of Goettingen. One of them, anthropologist Susanne Hummel, confirmed that Huchthausen and Lange share the longest proven family tree.
They found the bones of 23 people -- nine females and 14 males -- along with what appeared to be cult objects, prompting speculation among scientists that the cave was a living area and a sacrificial burial place.
Scientists found that the bones had been protected from the elements by calcium deposits that formed a protective skin around the skeletons.
The remains turned out to be from the same family group that had a distinctive and rare DNA pattern.
When 300 locals were tested with saliva swabs as part of the archaeological research, two local residents turned out to have the exact same genetic characteristics: Manfred Huchthausen and Uwe Lange.
"I could not believe this at first, but I think it's truly fascinating," Huchthausen, whose family has lived in the area since the 18th century, told ABC News.
The skulls have been reconstructed using 3-D computer techniques and are now placed at a museum in nearby Bad Grund.
Huchthausen has been to the museum, saying he found it "awesome" to see his ancestors.
He said he has received many calls from across Germany since the archaeologists published their findings.
"People are interested to find out what it is like to be able to trace back the family roots for 3,000 years, and I can tell them, it's awesome, it's sensational, it's fascinating."