Archaeologists Uncover a Medieval Floor Made of Bones

Hundreds of years ago, someone in the Netherlands concluded that the best way to fill the gaps in their floor was not with tiles, but with bones.

Municipal archaeologists working in the historical center of the Dutch city of Alkmaar have uncovered a historic floor partially tiled with animal bones. This rare feature, announced in a December 13 municipal statement, has only ever been documented in the province of North Holland, usually in 15th-century floors.

“We were very happy to have the opportunity to see this bone floor with our own eyes. It is always a privilege to uncover something from a bygone era and add new information to the history of Alkmaar,” Nancy de Jong, an Alkmaar municipal archaeologist, said in the statement.

The bones are parts of cattle metacarpals and metatarsals (foot bones), and were all cut to the same size. Despite how worn the floor is, archaeologists were able to detect a kind of pattern to the bone arrangement. Specifically, the bones were placed vertically, with either the ridged end or the sawed-off end facing upwards.

Archaeologists have seen this sort of thing before, having previously discovered similar bone features in floors in Hoorn, Enkhuizen, and Edam, with the Hoorn floor displaying a particularly similar pattern. Experts are now wondering whether this may have been a common 15th-century flooring solution or design in the Netherlands.

Archaeologists have yet to date the recently unearthed bone floor. The corresponding house was built at the beginning of the 17th century, but that doesn’t necessarily mean the floor itself is from the same century. In fact, it was not uncommon for new houses to be built on top of older foundations, according to the archaeologists, meaning the floor could conceivably still date to the 15th century, like most of the other bone floor examples.

Possibly even more interesting than the date is the question of why someone would choose to fill the holes in their floor with bones. Tiles were not expensive at the time, the archaeologists explained, so there was no obvious economic advantage to using bones. Perhaps, then, they were meant simply as a filling, and not as tiles. The team also hypothesized that the feature might have made sense in the context of the type of craft produced there.

“There are an awful lot of hidden stories still preserved, waiting for our team of archaeologists to come and find them,” said Anjo van de Ven, an Alkmaar municipal representative for heritage. “I’m always excited when they call me with an update on a find. What cool thing have they discovered now? – I think.”

Ultimately, the mystery of the bone floor persists, but hopefully not for long as the archaeologists continue to investigate the find. In the meantime, the rest of the world has clearly discovered a new long-lasting flooring solution.