​Alvars are dry limestone areas covered with a thin layer of soil and vegetation that thrives on lime. Besides the limestone and dolomite areas of North and West Estonia, alvars can be found only in Sweden, on the islands of Gotland and Öland, and to some extent on the Ahvenamaa islands. In places where the limestone is quite close to ground, only low vegetation or junipers grow. With the end of pasturing, several typical alvars have begun to overgrow with shrubs.