What we see is just a façade/plaster. Behind a façade there is a whole story hidden of people who made it. Amount of work, and materials is not visible. Most of the passers by just see monumental façade, an end work. We see it as a complete thing, but we often do not see that in fact its being constructed from many different pieces. It was a work of many people to do it, many crafts were used to that.