At Oslo's Viking Ship museum, a team of engineers has begun work to ensure a new home being built next door does not prove fatal for three vessels that have survived for a millennium or more.
The new building is necessary to protect the wooden ships, two of which date from the ninth century and the third from the tenth century, which are at the mercy of temperature changes and humidity in the current museum.
But the vibrations caused by construction are also a threat to ships so fragile their weight alone is enough to cause them to crumble. The engineers are building steel girders around them to protect them during the upheaval.
"If we keep displaying them as they stand today they will end up in pieces," said Haakon Gloerstad, director of the Museum of Cultural History, which owns the Viking Ship Museum.
Looters stole some of the artefacts from the three ships, named Oseberg, Gokstad and Tune after the places where they were found. Much survived, however, including a waggon, textiles, sculptures of animal heads and three sleighs, which are unique.
"The Viking ships are wonders similar to the pyramids in Egypt and Tutankhamen's grave," Gloerstad said - and they are least as vulnerable.
While the ships will be lifted in their protective metal casing, the sleighs are being moved on a rail track, centimetre by centimetre, to a chamber for their safety. It took 17 hours to move the first sleigh 70 metres (230 feet).
"This wood is now incredibly fragile: you could make crumbs out of it, it would just fall apart between your fingers," said head engineer David Hauer, who is supervising the move after years of careful planning.
The new museum will open in 2026, a hundred years after the ships' current home was opened, ultimately attracting ten times more visitors than it was designed for.
Until it closed in September last year to allow preparation for the move, it received around 500,000 visitors per year.
Meanwhile, Oslo's tourists are disappointed.
"We heard a lot about it and were really looking forward to have a look at it," US tourist Shalin Patel told Reuters.