Iron Age cairn sites often contain a variety of
materials, including bones, pottery, burnt clay and iron slag. Many of these
cairns have been interpreted as graves. In many cases, this has turned out to
be true, like in the case of the earth and stone mixed cairn excavated in 1980
at Roismala Ristimäki (located in Sastamala, Finland). When examined closer,
this monument – as well as probably other similar sites – reveals a more
complex content. It is realised that chronology, formation as well as
interpretation are not as straightforward as may have been previously
anticipated. In the case of Roismala Ristimäki, the dating of an inhumation
burial to the Late Roman Iron Age has been confirmed. Furthermore, one unburned
human bone found above the main burial has been dated to the end of the
Pre-Roman Iron Age or to the Early Roman Iron Age. From the cairn above the
burial, which contains an abundance of pottery, burnt clay, animal bones, etc.,
radiocarbon dating places this material at a range that spans several
centuries, from the Migration Period to the Merovingian Period. The results
point to the probability of several stages of accumulation or construction, and
that the cairn consists of mixed contents. The complex formation process is interpreted
as involving ritualization of the site.