From 3D to the cross section
The relief could be represented in several ways : 2D or 3D. The data for each are the same but the keys to read them are different.
Contour line of 25 m
Cross-section in 2D
Contour lines are formed by connecting points at the same altitude
Note : for cross sectional and 3D views, the altitudes are overestimated compared to reality. They are not the same scale as the horizontal distances.