A 2,000-year-old runestone unearthed in Norway is the world's oldest such stone - and contains a mysterious inscription.
The sandstone rune could date from the time of Jesus Christ, according to Oslo's Museum of Cultural History.
Made up of the unknown word 'idiberug', the inscription may be a reference to the person lying in the grave.
Professor Kristel Zilmer, of the University of Oslo, said: "This find will give us a lot of knowledge about the use of runes in the early Iron Age. This may be one of the first attempts to use runes in Norway and Scandinavia on stone."
Sometime between 1,800 and 2,000 years ago, someone stood near the Tyrifjorden lake – to the west of Oslo – and carved runes into a 31-by-32cm block of reddish-brown Ringerike sandstone.
The person spoke an early form of the modern Nordic languages used in Scandinavia today.
Zilmer said: "Having such a runic find fall into our lap is a unique experience and the dream of all runologists. For me, this is a highlight, because it is a unique find that differs from other preserved rune stones."
She added: "The text possibly refers to a woman called Idibera and the inscription could mean, 'For Idibera'.
"Other possibilities are that idiberug is the rendering of a name such as Idibergu/Idiberga, or perhaps the kin name Idiberung.
"The stone has several kinds of inscriptions. Some lines form a grid pattern and there are small zigzag figures and other interesting features.
"Not all inscriptions have a linguistic meaning. It's possible that someone has imitated, explored or played with the writing. Maybe someone was learning how to carve runes."
Older runes have been found on other items, but not on stone.
The runestone was discovered in autumn 2021 during an excavation of a grave near Tyrifjord in a region known for several monumental archaeological finds.
Items in the cremation pit – burnt bones and charcoal – indicated that the runes likely were inscribed between 1AD and 250AD.
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