This video shows something that very few people have had the opportunity to witness: the inside of the Lego factory, with no barriers or secrets. I filmed every step in the creation of the brick. From the raw granulate stored in massive silos to the moulding machines to the gigantic storage cathedrals to the decoration and packaging warehouses, you will be able to see absolutely everything, including the most guarded secret of the company: the brick molds themselves.


While the storage areas are the most impressive part of the factory, I have to admit that nothing had prepared me for the scope and complexity that is required to make and pack 19 billion bricks every year. The scale of this factory, specially compared to the tiny bricks it produces, is absolutely breathtaking.

The warehouse and the mold room

We started in the main warehouse, which is half a kilometer long. Here they house the silos holding the raw plastic granulate. Through them, 60 tons of this material is processed every 24 hours. These towers are connected to the moulding machines through a labyrinth of tubes that push the granulate mixtures in a permanent tin-pitched rumble.


It’s the digestive system of the enormous factory, always feeding the moulding lines through the tubes and moving big boxes full of pieces-using conveyor belts-into the storage area in an endless and precise dance which never ends: this factory works around the clock to fulfill the worldwide thirst for Lego.

The moulding machines

Everything is recycled in the factory. The plastic granulate itself is a by-product from diesel, and whatever is discarded in the manufacturing process gets recycled. The leftover parts from the mold-the plastic that fills the channels that take the hot plastic into the piece negative-fall down the machine, gets ground up, and put back into the production cycle. Any other waste, like faulty pieces or the transparent plastic used to clean the inner tubes when they need to change the production color of a moulding machine, are also ground up and sold to other companies for the production of other things, like pipes and even heating oil.

The machines produce more than two million pieces per hour, churning incessantly into color- and bar-coded boxes. I looked around and I couldn’t see many people. A woman was in one of those endless aisles looking at a few moulding machines with big “QT” signs on them. She was in charge of quality testing, making sure that the production was going perfectly.

At one point I was taking photos of a box of full of yellow bricks, and suddenly the machine stopped working. Fearing I had done something wrong, I saw a big wonky box coming from the distance, some kind of weird transport with strange sensors on the top, straight from a moisture farm on Tatooine or a spice mine in Dune. I stepped back, instantly realizing it was one of the many factory robots.


This transport bot was answering the call of the central mainframes, the brains of the Lego body that control every aspect of the process at all times. The mainframes had stopped the production of the machine, following the signal of the sensor next to the box and sending the signal to the robot, alerting it that it had to harvest the crop of bricks. The robots travel down the aisles autonomously, picking up boxes and leaving empty ones so production can be resumed.

The storage cathedrals, decoration and packaging

The robots then put the boxes in the conveyors, which move them into the storage cathedrals (click here to see a complete report on them, the following video only has a brief summary). There, the huge cranebots lift them to the heavens, placing them in endless towers of boxes. There are four of these cathedrals in the Lego factory, and no humans are inside. The mainframes know what it is inside at all times, and order the cranebots to retrieve boxes and send them to decoration and packaging, where Lego sets take their final form.


Here, the Lego pieces may take two ways. One is to go straight to the packaging lines. The other is to go into decoration. Decoration is the most expensive part of the Lego process. Here, the pieces are individually painted with absolute precision, like you can see in detail in this video.


In the packaging lines the pieces are distributed: they are dumped into the machine, which separates them one by one, then counts them using optical sensors, and placed in a generic small box. I watched in amazement, seeing how the pieces fell into these small boxes on a very small conveyor. At every step, one, two, three or whatever amount of pieces will fall into the box, according to the instructions of the set in production.

Along the way, high precision scales measure the weight of the box. The computers know exactly how much a box has to weigh at any stage, indicating that the correct number and kind of pieces are inside. If there’s a variation of a few micro-grams, the alarm jumps and an operator grabs the box, sorts the pieces, and puts the box back into production.


Once the box is complete, the contents are dropped into the plastic wrapping machine, which makes a bag with the pieces inside. The box are then dropped inside another box, and passed into another production line, where more bags would be added until all the set pieces are in place, ready to be packaged and sent to shops all around the world.

As I watched the boxes going away, being wrapped for shipping, I couldn’t help to have this feeling of absolute marvel. From plastic grains to full sets, everything controlled by computers and robots, in a scale that-given the size of most of these piece-stunned me. Next time you look at that Lego box full of bricks, or your collection of mini-figs, think about how complex and elegant the whole production process is. Your “toy” will have then a completely new dimension.