Cezanne uses many diagonals as he attempts to capture different views of Mont Sainte-Victoire. While not a realist painting, some are more realistic others. Take picture 4 above. That painting relies more on the blocks of color in creating the landscape instead of carefully planned lines and measurements of perspective. Certain squares of colors come together to show houses amidst the trees. In picture 2 and 3, there is more detail drawn out, and Cezanne locates us by placing the mountain beyond nearby trees.
Personally, I find these paintings interesting because they seem childlike to me. Especially picture 1, they appear to be just really good crayon paintings. I am well aware that I could never make anything like that and am in no way belittling it. But, there is a simplicity and vibrancy in some of these series pieces. His concentration on continually depicting the same landscape from different angles and times of year is refreshing as well. All are beautiful and yet his constant repetition seems to portray a search for perfection and satisfaction as well.