The woods is dominated by Scots pine, and deciduous trees include sessile oak, hornbeam, and beech.
[2] The Udin Woods encompasses nearly the entire area bounded by the road from Kranj to Golnik on the east, the old road from Kranj to Tržič on the west, the A2 freeway on the south, and Mount Križe (Slovene: Kriška gora, 1,473 meters or 4,833 feet) to the north.
Karstification took place during the Holocene interglacial, when limestone terrace flooding provided good conditions for the development of karst under a warmer climate and with abundant water.
Springs appear at the contact points; their output is less variable than in Dinaric karst areas and they have a constant flow.
There are visible remnants of moats and elevated rings where wooden palisades protected the settlements.