Bihać M-5 - Štrbački buk - Kulen Vakuf - Martin Brod

http://nationalpark-una.ba/bs/

National Park "Una" is spread through the valley of the upper stream of the river Una as well as through the valley of the river Unac, right tributary of Una, all the way to the river Krka in the west. This area represents a unique natural complex in this part of Europe, very valuable for the conservation of the total landscape and biodiversity, especially because of:

- Position on the border of three climate areas;
- Karst formations and hydrology, which are unique in European terms, together with the basin of Korana and Krka;
- Landforms that created one of the few natural routes to the Adriatic Sea;
- Mosaic of habitats, high diversity of plant and animal species, and the presence of relict and endemic species;

In terms of cultural and historical area, this area abounds with a rich heritage of archaeological sites and historical monuments, and the special position of the area on the transit line to the sea led it under the influences of many cultures in the past, from where the rich archaeological sites date, remains of medieval fortresses and religious buildings of different faiths and cultures. The area of the National Park is located on the extreme western part of Bosnia and Herzegovina, in the municipality of Bihac and belongs to the Una- Korana plateau, and covers valley parts of the river Una and Unac and orographic slope Pljesivice and Grmeč, that is Osječenica. The specificity of the river Una is its excessive length of "travertine" flow, with a range of associated phenomena (caves of tufa, travertine islands, barriers and waterfalls), and with extreme forms of pits (Martin Brod, Kulen Vakuf, Klisa, Lohovo) and the cliffs of a canyon-type, upstream and downstream of Martin Brod and downstream of Štrbački buk.

River Unac has a characteristic shape of its karst flow, especially in its lower part, where it sinks and rises more times at the passage through the canyon, and at the end at the Black well, which by its characteristics and beauty belongs to a particular natural phenomenon. Lowland part of this protected area is located at an altitude between 220 and 450 m n.m., and is oriented in northwest-southeast direction. It is especially important to emphasize the connectivity of the river Una, as the basic natural phenomena intended to protect the local population that resides in this area for centuries, which recognizes the value of the river and the area for their own survival, and its uniqueness, which is valuable for preserving local and regional level. Initiatives, first, the UNESCO nomination, and later for the designation of the area as protecred, largely derived from the initiatives of local communities in this area. This special relationship between the river Una (Una lat = one, one) and the local population is one of the important characteristics valuable for the preservation and protection of the area.