Harghita Mountains are part of the Eastern Carpathians, also representing the southern part of the volcanic group that stretches up north to the Ukrainian border.
The western slopes of Harghita Mountains are in contact with the Transylvanian Plateau, while they border Gurghiu Mountains to the north, Ciuc, Bodoc and Ciomatu mountains to the east and Baraolt Mountains to the south.
Harghita belongs to the group of mountains with medium heights, its highest point being reached in Madaras Peak, 1800 m, thus rising with approximately 1200 m over Olt defile.
The last signs of volcanic activity are the hundreds of carbonic mineral water springs and the moffetes with their well known curative effect. On Harghita Mountains we find volcanic conglomerates alternating with sedimentary rocks.
In the lower levels flora is represented by mixed forest of oak and beech followed up by spruce forests and in the upper level juniper, dwarf pine, bilberries and alpine pastures.
In Harghita forest we can find brown bears, wolfs, lynx, wild boars, deer, squirrels, mountain cocks, woodpeckers and eagles.