Geology of Finland

Finland, like most of Skandinavia, belongs to and old craton, and thus consists mainly of crystalline rocks. It is not difficult to see, that this makes all sorts of karstic phenomenon, like caves, rather unlikely. Finland has less than a thousand caves, and they are typically very small. The biggest one is Torhola cave at Lohja, which is slightly over 30 meters in depth.

But Finlands few caves offer some unique experiences. Korkia-Maura cave in Inari has a floor of permanent ice, which is used as a skating rink. At Lampivaara, in Sodankylä, a cavity was discovered in which two-thirds of the roof coated with amethysts. This small cave is only 1.50 m in diameter, and could also be called a huge geode.

Susiluola cave (Wolf cave) in Kristiinankaupunki is the most famous archaeological cave of Finland. This country was covered completely by shields of ice between one and two kilometers thick during the last Ice Age. This cave contains the oldest remains of mankind in Finland. The remains include fire places and stone implements whose age has been determined to be 120,000 years old.

Finland has virtually no karst caves, and approximately 70% of its caves were formed by the ice. The caves are either of tectonic or neotectonic origin.

Beneath the natural caves, there are numerous artificial subterranea. And the crystalline rocks bear some valuable minerals and metalls, so several mines exist.