Archaeologists discover a mysterious floor made of BONES in the red light district of a Dutch city

When excavating the floor of a building, archaeologists can usually discover ancient earthenware tiles or a beautiful Roman mosaic.

But a team in the Netherlands has discovered a much more bizarre find: a floor made of bones.

The carefully arranged bones were found in a building in the Achterdam, a red-light district in the Dutch city of Alkmaar.

The bones come from dead cattle and may have been laid during the construction of the building around 500 years ago, experts believe.

However, the bones were laid centuries before Achterdam became famous as a red-light district.

The municipality of Alkmaar, Municipality of Alkmaar, said in a statement: ‘The question is of course why bones were used to fill the tiled floor.

‘Tiles were not particularly expensive and were often used. It is possible that the bones were placed there for a special reason.

‘Perhaps because it fitted in well with the craft that was probably practiced here. It could also have been a cheap way of filling.’

Experts from the municipal heritage department were carrying out renovation work on the house – which was built in 1609 – when they found the bones.

The bones were covered with a thin layer of loam – soil that is a mixture of sand, silt and clay – and then covered with a recent tiled floor.

The exact period in which the bones were laid is still under investigation, but experts estimate that it could be as early as the 15th century.

“The building itself was built in 1609,” Nancy de Jong, archaeologist for the municipality of Alkmaar, tells MailOnline.

‘But it is possible that the foundation and lower level of the floor where the bones were found are much older.

‘It is common for houses to be built on older foundations.’

Alkmaar is believed to be about 1,000 years old, as the earliest mention of the city is in a 10th-century document.

The bones are metacarpals and metatarsals from the lower limbs of cattle, all cut to the same height – but exactly why they were used instead of tiles is unclear.

Adding the carefully arranged bones could have been done if there were not the required number of tiles, or to fill a gap left by damage.

“We were very happy that we had the opportunity to see this bone floor with our own eyes,” said de Jong.

‘It is always a privilege to discover something from a bygone era and add new information to the history of Alkmaar.’

Although the historical use of bones in this way is unusual, it is not unprecedented in the Netherlands – but only in the northern province of North Holland.

In the past, these types of floors have been found in the cities of Hoorn, Enkhuizen and Edam – which, like Alkmaar, are located in North Holland.

In the Hoorn example, the vertically placed bones have also been used in combination with a tiled floor, which indicates that this was a deliberate tactic of North Holland tilers.

According to experts, the bones will be further examined to see if there are indications of how exactly this floor was used.

Anjo van de Ven, heritage councilor at the Municipality of Alkmaar: ‘Discovering this floor is extremely interesting.

“There are still so many hidden stories waiting for our team of archaeologists to come and find them.”

The Achterdam – a 150 meter long street with window prostitution on either side – is located in the old center of Alkmaar, known for its traditional cheese market.

Since the Middle Ages, paid sex has been available in Alkmaar, although at the time the city’s red light district was the Vrouwenstraat, slightly further south.

The Christian church considered sex work objectionable, but also necessary to protect other women from rape and virginity.

In 1973, the first brothel on the Achterdam – at the time still a street where mainly traditional craftsmen such as barrel makers, hat makers and rope makers lived – was opened.

This was the starting point of Achterdam as a red light district, the only place in Alkmaar where window prostitution is allowed.

Unfortunately, Achterdam has since been the scene of human trafficking and even the murder of two prostitutes in 1996, although since the turn of the century rooms have only been allowed to operate with a permit from the municipality.