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Peering at Old Danish Privies

Note: This blog post was co-authored by Sydney Sapper

Our friend Sydney recently went to Copenhagen, Denmark. She visited The Round Tower (Rundetaarn) and saw the old privy there. The Round Tower has the oldest observatory in Europe (the current one dates back from 1929) and is one of the most memorable buildings in Copenhagen. Sydney shared some great pictures and details about the old toilets that we are sharing in this blog post for your enjoyment.

The Round Tower in Copenhagen (Credit: wiredforiego (FLICKR))

The Round Tower

King Christian IV built the Round Tower in the early 17th century (finished in 1642). He built the tower as an observatory to continue the work of astronomers such as the prolific Tycho Brahe (who never went to the Round Tower). Astronomy was a big deal in the 17th century because countries could use star maps while sailing oceans to establish new colonies.

Fun tangential facts about Tycho Brahe: He wore a silver nose! Also, he wrote about how the Cassiopeia supernova was far away from our galaxy, even though it was bright. He was also responsible for creating an accurate star map that included the planets, which helped Kepler develop his astronomical laws.

The Round Tower also hosts a church and the Copenhagen University book collection. The library had a lot of great and notable visitors in its life. One visitor included the famous fairytale writer Hans Christian Andersen. Andersen frequented the library in the 19th century while writing stories, such as The Little Mermaid and The Princess and the Pea.

The Privies

Images of the old privies at The Round Tower (Credit: Sydney Sapper)

The Round Tower opened with two privies included along the spiral staircase - one at the top for astronomers, another halfway up for the library users. Technically, these were privies, as they weren't outside (more often called outhouses now). Still, the Round Tower's privies functioned similarly to other privies, meaning that it was merely a hole with a drop into a hole where the waste accumulated.

People smoked pipes in the privies frequently, which tourists can still see the smoke residue on the walls.

The privies had a shaft system hollowed out through the walls that dropped the waste from the toilets through a sealed shaft. The shaft had no outdoor ventilation and had to be emptied internally. This sanitation system could be considered one of the largest and earliest septic tanks we know about. However, this sealed shaft ended up making….the place stink something fierce.

Without ventilation, all of the decomposing waste in the privy system had nowhere for the gasses (and smells to go). Privy users smoked in part because of the smell, which the vaulted toilet could not ventilate. That probably also meant the toxic gasses (such as methane and hydrogen sulfide) from decomposition, as well as the memorable smell from uric acid that lingers from urination, wafted around. It's a miracle there were no incredible explosions of note from this system.

Don't worry, they don't smell anymore. The Round Tower now has modern flush toilets available for tourists to use on their visit, right next to the old privies.

Images of the holes in the ground for the privies to drop their waste, and the direction of the storage tank

(Credit: Sydney Sapper, Rundetaarn)

The privies emptied out the waste into a holding tank under the tower that was so large (about 12 cubic meters, about the size of NYC's smallest apartment) that it took about 50-60 years to fill up. This is really impressive and means that by the time the holding tank filled up, most of the waste was completely composted into basic soil. In 1921, the city removed nine loads of decomposed waste from the holding tank before installing water closets to replace the privies.

Copenhagen's Old Water Troubles

Copenhagen wasn't without its sanitation issues, of course. By the 1800s, the Round Tower was used as an unofficial public urinal, and the smell embarrassed the walking passerby. In the 1840s, Copenhagen's drinking water was pretty disgusting like the rest of Europe. The water they had was a breeding ground for mosquitos, leeches, amphibians, and rotting fish. They even joked that their water was "the famous lukewarm eel soup".

In 1844, when the area was cleaning up the street gutters, the city found a hole between the water pump source and the city's sewer line, meaning that all kinds of nasty effluent found its way into the water system. Around the same time, entrepreneurs started to schlep water from springs outside the city and sell their liquid goods. Soon after these discoveries, the city started importing water from the outside springs and opened a water stall outside the Round Tower. They had installed an underground tank to hold and cool the water. The city constructed its current underground sewer system in 1857, further helping separate their drinking water from cleaning out toilets and privies alike.

A special thank you to Sydney Sapper for the pictures. An additional thank you to the Round Tower’s website for some fantastic historical articles.


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