Šmarna gora is an isolated hill – an isolated elevation on the plain with two peaks, Šmarna gora and Grmada. In the Local Lexicon of Slovenia it is enlisted also as a hamlet, therefore it is not just a Gora (Gora meaning mountain).
Šmarna gora was once as a mountain range connected to the Polhov Gradec Dolomites and to Rašica. The lowlands that we admire from the top faced towards the south and is named the Ljubljansko polje was at that time a hilly region, on the other Northern side the part of the area was sinking. This is how the landslide in the area of today's Ljubljana Basin whose surface got the form it has today only after the period of glaciation.
The river that flowed by before Sava was more on the North in the direction of West to East. Later on it flowed between Šmarna gora and Rašica and then one more time changed its bed between the hills of Polhov Gradec and Grmada. The river was bringing a great quantity of spoil, sand and clay. The river deepened its bed and filled it with alluvium in alternation. And at the same time the river's bed was changing. One can still observe the terraces with its banks which are full of trees and shrubbery among the terraces.
Šmarna gora is exceptional due to its diverse stone foundation (see geological features) in which one can find the fertile floor of different qualities. The geographical location enables several climatic influences. From metre to metre the altitude, exposure (location according to the cardinal points) and slopes. If we add the human intervention into the space and nature, together we get an exceptional diversity of fauna and flora. All the animals and plants here namely have their ecological requirements (warmth, moisture, light), and to many of them Šmarna gora serves with the right combination.
Although it is little, the cave Matjaževa jama is a precious site. It is a real dripstone that came with a natural window on the ceiling. It can be found in the hillside of Gradišče or Matjažev hill some ten metres about the lowlands in Zavrh.