The aim of this interactive teaching and learning resource is to learn to measure the distance between two geographical points on a map and to find out the height difference and the slope between them. With a chosen starting point and destination point, the contour lines are interpreted and a simple calculation is made. Aimed at students aged from 10 to 14 years.  https://www.ign.es/recursos-educativos/descubre-territorio/desnivel.html