Pythagoras is a hot bulb engine factory founded in the early part of the last century. In an environment where you can still smell the foundry dust and engine oil you can get the feeling of what it was like to work in a factory that, with many others, built Sweden as an industrial nation.

Here is food for all the senses. Even to this day the wheels of industry keep turning. Just look, smell and listen to the laths and mills as they are driven by transmission belts up in the ceiling. Hear the regular thump of the hot bulb engines on the workshop floor.

The company Verkstads AB Pythagoras was founded in Norrtälje 1898. The company was to make a mechanical calculator, which accounts for the name of the company after the Greek mathematican and philosopher Pythagoras.

They failed to get the prototype calculator to work and as a result of this setback brought up a lock factory. They made locks, brass candlesticks, electric light fittings etc. At the beginning of the last century they researched and developed a hot bulb engine. The production of this type of engine was to be the main commercial product made in this factory. The engine company Pythagoras was for a long time the main industry and the most important work place in Norrtälje. It was from this factory in the little town of Norrtälje that they exported hot bulb engines out to every corner of the world.

Over the years the Pythagoras company was forced several times into bankruptcy and this led to a change in ownership. The business slowly died and finally came to an end in 1979, when the last employee died. Throughout the 1980’s a group of enthusiasts worked hard and saved the factory, with its complete collection of original metalworking tools and machines, from local property developers.

Today the factory has once again come to life as a working museum with the original tools and machines, offices and a watchman’s cottage with its interior from the 1940’s. The museum has been listed as one of the most important remaining intact industrial sites for the foundation and development of Sweden as an industrial nation. What you can experience here inside the factory with its belt driven machines and their tools; the offices and archives with technical drawings, orders and receipts is a picture of the rise and fall of a Swedish industrial company from the last century.When you step into the workshop you take a step back into the past.



-the womans’s movement
In the courtyard beside the main factory building stands a red painted cottage, the caretakers cottage. Here lived the caretaker and his family.

With the help of information from former residents an authentic 1940’s interior has been recreated. The family only had the use of half of the building as the other half was used for storage. Today this houses different temporary exhibitions.

For more information and opening hours please phone 0176-100 50 or e-mail to