From gravel to esker and ice to lake

Vierumäki is located on the Second Salpausselkä ridge and bears the marks of the Ice Age. The narrow and steep-sloped ridges of the Lemmenharju esker, lined with small lakes, offers a view over Finland's most internationally renowned geological heritage. The ice-marginal formations of Second Salpausselkä formed about 12,000 years ago.

As the continental ice-sheet receded, the Lemmenharju esker, located on the north side of the current Sports Institute, was formed from the gravel and sand carried by the stream. The receding ice left behind enormous blocks of ice that were buried under the sand and gravel. As the ice blocks melted, some of the kettle holes left in the ground were filled with water. One such kettle lake is the greenish, rapidly deepening Valkjärvi lake.