Iina Nurmela, Satu Kurvinen and Eric Mwai

The Finnish topography used to be the way it is today even before the Ice Age. The influence of the glacier on the differences in altitude was not very significant but it had a significant influence on the contour. 

The flatness of Finland is due to the old age of the Finnish bedrock. The Finnish bedrock is mainly Archaean. About one third of the bedrock is 2.5 billion years old. In our bedrock there are traces of at least two ranges of mountains: about 3 billion years ago occurred the presvekokarelidian folding and about 2 billion years ago occurred the svekokarelian folding. Nowadays only the bed of these folded mountains exists. The existing higher peaks are like knotholes in an old wooden floor, which are harder and have resisted weathering. This might be due to a hard type of rock, to the schistosity of the bedrock, or to other structural characteristics. 

The share of the higer peaks described above is smaller compared to the intensity of the tectonic movements that occurred after the folding. The most significant movements have been the faults, due to which rifts and folds (horsts) have formed. After the forming of these rifts and folds, the most important factors that have affected our contour have been external factors. Finland is really flat: the average height is only 152 m. The average height in Europe is 330 m and in the whole world 840 m. The flatness in Finland is due to the fact that the bedrock has weathered almost down to the sea level, i.e. the final stage of erosion. The hardest weathering happened when Finland was located on the tropical climate region. 

Finland is mainly lowland area, i.e. less than 200 m high. The border between lowland and highland areas runs roughly from Kolari to Kemijärvi to Pielinen. One could say that the more north and east you go, the higher the area gets. Southern Finland is fairly low area, but there are some higher points. 

The altitude zones of Finland according to Matti Tikkanen