Look carefully and you'll see all kinds of hidden stuff. There are major differences in this category, from simple drawings to true works of art (look at the landscapes !). Keep your mouse on the information icon and the answer will appear.
There are two surprises in this painting. At first sight it seems that you are looking out of a window. Then you notice that is actually a painting standing in front of the window. It blends in with the background. When you look at the painting you see there is only one tower ! What seemed like the right tower is a street . . . Number of ratings : 60.