Southern Foothills of the Trnovo Forest
The entire area of the southern foothills of the Trnovo Forest, which delineates almost the entire Vipava Valley in the north, is a natural protected area. Articulated over the course of millennia by geomorphological processes, the steep slopes and precipitous walls of the southern foothills rise in tiers over the Vipava Valley. Thus, the entire area of the landscape park is marked by natural phenomena such as precipitous walls, inselbergs, natural bridges, abris and underground geomorphological shapes.
These spectacular foothills are where the Dinaric world meets the Submediterranean, merging and giving rise to many peculiar plants. The dry and wind-swept high Karst meadows feature habitats of edelweiss and Genista holopetala. A true botanical rarity is the hladnikia (Hladnikia pastinacifolia) which can be only found in the rocky grasslands and rock crevices of the Trnovo Forest and nowhere else in the world. It’s a paleondemite and grows only on 4 km2. It can reach 40 cm in height, and has shiny, split leaves with a serrated margin and a white inflorescence.
The Submediterranean dry grasslands are home to many species of butterflies and birds. Also intriguing are animal fossil sites.
The Southern Foothills of the Trnovo Forest are best reached on foot, over a myriad of hiking trails criss-crossing the hills. Hikers are enthralled by the natural sights along the way. The most famous sights are the two natural windows or natural bridges: the first one is known as the Otlica Natural Window (Otliško okno) and is situated on the edge of the plateau near the village of Otlica overlooking Ajdovščina, whereas the second one is Skozno, which is a natural bridge above Lijak Stream, on the precipitous edge of the Trnovo Forest. There also two quite intriguing karst springs. The spring of the Hubelj above Ajdovščina is the largest water source in the Vipava Valley, and the spring of the Lijak is a special type of karst spring.
The foothills abound with other, lesser-known natural sights as well. Sitting close to St Mary’s Church above Vitovlje is the lake of Vitovsko Jezero, which is not only the highest lying but also the only natural lake in the entire Vipava Valley. Lying on karst terrain, on a layer of impermeable flysch, this small body of water is peculiar due to its geographical location and origin. Next, overlooking the village of Črniče, is an awe-inspiring gorge with steep and precipitous cliffs, which was carved into the rock by the Konjščak Stream.