From geological aspect, the basic substrate of the territory of National Park Mavrovo belongs to the Western Macedonian Geotectonic Unit. The bed rocks, which are of various age and mineralogical structure, could be grouped into three geological formations: Paleozoic metamorphic and magmatic rocks; Mesozoic sediment rocks; and Quaternary slates.
Under the influence of tectonic movements, larger morpho-tectonic forms including mountains, valleys, mountain peaks, mountain saddles, tectonic shifts, while under the influence of external forces a variety of geomorphologic forms had been created.
The Korab Mountain Massif rises from the right side of the Radika River valley, i.e. on the Western side of the National Park Mavrovo, in the far western part of Macedonia, along the Macedonian-Albanian border, from the mountain peak Sherupa (2,092 m) in the North, to the mountain peak Rudina (2,238 m) to the South. The Korab Massif is composed of three mountains that are mutually interconnected in direction from North to the South (Korab, Deshat and Krchin).
The Shar Planina Mountain massif rises in the North-east and partly in the Northern part of the Mavrovo National Park. Within the boundaries of the National Park, only the farthermost South-western parts of this massif are included; southward up to the Mavrovo Valley and Mavrovska Reka River, westward up to the Radika River and northwardly to the watershed with Sherupska Reka River.
The Bistra Mountain rises in the East and South-east part of the National Park Mavrovo, to the South from the mountain pass Vlainitsa (1,310 m); through the Mavrovo Valley and Marvrovska Reka to the mountain pass Yama (1,507 m), the Valley of Mala Reka River and the valleys of its tributaries Garska and Yamska Reka River. Westward the Bistra Mountain stretches to the Radika River and eastwardly to the Kichevo Valley.
Altogether, within the boundaries of the National Park Mavrovo, 86 mountain peaks higher than 2,000 m are present, of which on the Mountain Korab 41, on the Mountain Deshat 7, on the Mountain Krchin 7, on the Mountain Bistra 15, and on the Shar Planina Mountain 16. Of the total number, six mountain peaks are higher than 2,500 m, all of them situated on the Mountain Korab. In the National Park Mavrovo, 23 high mountain passes are present, through which the Park with the neighboring areas is connected. Among them, the highest high mountain passes in the Republic of Macedonia are present, like: Golema Korabska Vrata (2,063 m), Mala Korabska Vrata (2,465 m), Deshat (2,020m), and Sveta Nedela/Suva Bara (2,065m).
Of the most significant relief forms created as a result of external forces, we shall mention the river beds with canyons and the underground karst relief forms (caves). In the National Park Mavrovo, within the Radika River watershed, altogether 16 canyons and 42 caves have been recorded.
