Significant landscape Sunjsko polje covers an area of 20,270.25 ha. It is located in Sisak-Moslavina County on the right side of the Sava River, spreading throughout the city of Sisak and the municipalities of Sunja, Hrvatska Dubica and Jasenovac. Sunjsko polje includes the area along the Sunja River and its tributaries. Together with Nature park Lonjsko polje it forms an ecological unit and as such is a site within the Natura 2000 network - "Donja Posavina", a conservation area important for birds.
Sunjsko polje was proclaimed as significant landscape on 2 October 2013, with the aim of preserving its natural values. These values have been maintained for centuries through human coexistence with nature. Local inhabitants used Sunjsko polje for agriculture, livestock farming and forestry, which created conditions for the development of many ecosystems and the appearance of many species of flora and fauna.
The following types of tourism are encouraged and promoted in the area of Odransko polje: cycling and ornithological tourism (birdwatching).
Floodplain forests of pedunculate oak, black alder and field ash make up 50% of the area of Sunjsko polje. The remaining 50% of the area are wet and mesophilic meadows, nitrophilous grasslands and pastures.
Traditional grazing ensures grassland vegetation and prevents overgrowth of pastures. Also, these meadows are being mowed in order to ensure hay for winter feeding in stables.
In this way, meadows, which are an important habitat for protected and endangered bird species -like the corncrake (Crex crex) and the Montagu's harrier (Cyrcus pygargus) - are being maintained. The floodplain forests of this area are an important habitat for the lesser spotted eagle (Aquila pomarina), the white-tailed eagle (Haliaeetus albicilla), the black stork (Ciconia nigra), the middle spotted woodpecker (Dendrocopos medius) and the collared flycatcher (Ficedula albicolis).
Sunjsko polje is located within the ecological network Natura 2000 as a conservation area important for species and habitats - HR2000420 Sunjsko polje and as a conservation area important for birds - HR1000004 Donja Posavina.
Sunjsko polje, with all its contents, is an area of international importance and requires special care and attention in the course of future management. The distinct landscape values of this area are conditioned by the dynamic exchange of spacious livestock pastures, forests and villages with preserved traditional architecture of wooden Posavina houses. In addition, the area has an abundance of living ethnographic heritage - folklore tradition and folk songs, costumes and various folklore festivals.
Pastures are extremely important for the maintenance of extensive livestock, which is an important traditional economic activity of the local population. The local association of Posavina horse breeders preserves this endangered indigenous horse breed (Posavac horse).
Known about the unknown
Within the area of Sunjsko polje there is a small locality Dražiblato (20.63 ha) protected in the 1960s as a Special Ornithological Reserve.