The area around Village Kolatselga is rich in eutrophic herbaceous and herb-brown-moss fens in natural state. The mineral nutrition richness of these fens is due to the underlying carbonaceous rock (dolomites) and generates a high diversity of the flora and vegetation. The flora comprises four species listed in the Red Data Book of the Russian Federation (Cypripedium calceolus, Dactylorhiza traunsteineri, Myrica gale, Rhynchospora fusca) and a number of species red-listed in Karelia. Some of the associations found in these fens are also rare in eastern Fennoscandia and this area lies at the limit of their distribution range. Participants of the excursions will learn about the vegetation of four mire massifs; the composition of their flora and descriptions of their most typical associations can be found in appendices. Another aspect covered is the stratigraphy and vegetation dynamics during the Holocene in three mire massifs