Since the end of the middle ages are wooden shoes worn in many parts of Europe. Now it's mainly worn in the Netherlands. However, not many people wear those things. At many jobs, the wooden shoes are still used. It's also the famous souvenir for the foreign tourists. That's also why the most of the three million wooden shoes, which are made every year, are for the tourists.
The wood which is used for the wooden shoes, is poplar-wood. It has the advantage that it's rather long-wearing, so the wooden shoes will wear well.
In the past, the wooden shoes were hand-made, there were thousands of 'clog-makers' in the Netherlands. Since around 1950, it's possible to make wooden shoes with the machine.
The most of the work is taken over by shoe machines, but there are many things like before 1950. Of course, the good kind of wood, which is needed for a good quality wooden shoe. The tree has to be chopped immediately, and conveyed to the factory. Just like the clog-maker does, the stem will be divided into some parts. They do that with their hands, but almost everything which is left, can be done by shoe machines.
In special drying-rooms, the wooden shoes will be dried. But they have an extra problem now, which isn't there if it's hand-made. Sometimes, one wooden shoe shrinks more than the other from that pair. Because after the shrinking, they will be scoured, and then you got a pair with two different sizes. The shoe machines are so good now, that the wooden shoes get the same size.
If everything is in the factory, then you can make 20,000 wooden shoes a month if there are ten employees, so that will be 240,000 a year.