A building renovation in the Netherlands has led to a bone-chilling discovery: a centuries-old tile floor that's partly filled with sawed-off bones.
The bones aren't human, though — they're from dozens of cows.
The discovery, which has puzzled archaeologists, was made in Alkmaar, a municipality in the Netherlands known for its traditional cheese market.
Archaeologists were called in during the renovation of an early-17th-century building in the city's red-light district, according to a translated statement from the municipality of Alkmaar. They found that the tile floor was extremely worn due to intense use and that a gap in the floor was filled in with the leg bones of cows. Specifically, the bones were metatarsals and metacarpals, which in humans are the foot and palm bones, but in cows are part of the lower leg and ankle.
"We were very happy to have the chance to see this bone floor with our own eyes," Alkmaar city archaeologist Nancy de Jong said in the statement. "It is always a privilege to uncover something from a long-gone era and add new information to the history of Alkmaar."
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It is currently unclear when this bone floor was made, although similar examples have been found in the Dutch port towns of Hoorn, Enkhuizen and Edam and were dated to the 15th century, according to the statement.
Researchers are also unsure why chopped-up cattle bones were used in the floor, since tiles were not expensive at the time. It's possible that the bones were placed there for a particular reason, according to the statement, which was potentially related to whatever business was operating out of the building.
Alkmaar is the home of the Dutch Cheese Museum, and its cheese-mongering history goes back to at least 1365, with the first written mention of its cheese market in 1408. At the height of its prominence in the 17th century, Alkmaar traded millions of pounds of cheese, exporting it elsewhere in Europe and even as far as North America and the West Indies. But it's unknown if the cow bones in the floor relate to this longstanding cheesemaking tradition.
"Discovering this floor is incredibly interesting," Anjo van de Ven, councillor for heritage, said in the statement. "There are still so many hidden stories waiting for our team of archaeologists to come and find them."
Further investigation of the "floor of bones" is planned as archaeologists try to determine the extent of the bone floor and how it was used, according to the statement.
