It looked to be a routine excavation of what was thought to be a burial mound. But beneath the mound, archaeologists from the Norwegian University of Science and Technologys Museum of Natural History and Archaeology found something more: unusual Bronze Age petroglyphs. "We believe these are very special in a Norwegian context," says museum researcher and project manager Anne Haug.

The excavation in Stjordal, just north of Trondheim, was necessitated by the expansion of a gravel pit. Given that project archaeologists didnt anticipate that the dig would be very complicated, the museum researchers dedicated just three weeks to the effort.

Petroglyphs under a cremation site

Then came the surprises. First, it turned out that mound builders had used an existing hill as a starting point - which of course saved them time and effort. The hill itself made the burial mound even larger and more monumental than it might have otherwise been.

But researchers suspected there might be another reason for the choice of the hilltop when they uncovered the remains of two cremations, or rather a fire layer that also contained bits of bone. Underneath they found many petroglyphs, including eight drawings showing the soles of feet, with cross hatching. There were also five shallow depressions, Haug says.

Two boat drawings and several other drawings of feet soles with toes were also found just south of the burial mound.

LInk between burial mound and drawings unclear

This is a very special discovery, and we are not aware of other similar findings from Trøndelag County, she says. The tomb might have been deliberately constructed over the petroglyphs, probably as part of funeral ritual. Based on the type of characters and especially the drawings of the foot soles, we have dated the artwork to the Bronze Age, about 1800 - 500 BC.

Why there are foot sole drawings beneath the tomb is a puzzle. But if we interpret the find in terms of a fertility cult, it may be that the soles represent God and life-giving power. That means that you can have both life and death represented in one place, she says.

Unique in a Norwegian context

Haug says that there was a similar discovery in Østlandet, an area called Jong in Bærum, where petroglyphs illustrating foot soles were found under a tomb that dates back to the Bronze Age. In a Nordic context, this phenomenon is more common, and there are several examples where burials were combined with rock art, particularly petroglyphs of foot soles from Bohuslän, a World Heritage site in Sweden.

Its not yet clear if the grave was put in place the same time as the petroglyphs, Haug says. The dig began in September, 2010 and extended through the end of October, but the analysis is ongoing.

The scientists have found about 900 grams of burned bone, probably from one or more individuals; they hope to be able to carry out C-14 dating of the material and conduct more analyses so they can determine more about the gender and the age of the individuals in the grave.

Currently, we have found several human teeth, as well as what may be remains of human ribs. We also found an animal tooth that suggests that one or more animals may have been laid in the tomb along with whoever is buried there, she says. There were very few objects found in the tomb, but a flat corroded metal object was found in the burnt layer. It's hard to say what this was, but the object will be X-rayed for analysis.

Remains of a larger burial ground?

It is unclear whether the original burial site contained two grave mounds, or whether there was just one large burial area.

A burial ground in the area was first described in 1818 by Lorentz D. Klüwer, and archaeologist Karl Rygh also described the site in 1879. It is likely that the graves that have been excavated in the most recent dig are the last remains of this burial ground.

The rock art found at the site is a type called South Scandinadivan agriculture carving and is dated to the Bronze Age, from 1800 - 500 BC. The tomb probably dates to the transition between the Bronze Age and Iron Age, from 500 BC up to the year 0.

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Provided by Norwegian University of Science and Technology