The Mrežnica is a river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

 in Karlovac County

Karlovac County

Karlovac County is a county in central Croatia, with the administrative center in Karlovac.The city of Karlovac is another fort from the times of the Military Frontier...

, Croatia

Croatia

Croatia , officially the Republic of Croatia , is a unitary democratic parliamentary republic in Europe at the crossroads of the Mitteleuropa, the Balkans, and the Mediterranean. Its capital and largest city is Zagreb. The country is divided into 20 counties and the city of Zagreb. Croatia covers ...

.
It is 63 kilometres (39.1 mi) long and its basin covers an area of 64 square kilometres (24.7 sq mi).

Mrežnica is considered special due to its large number of waterfalls, totalling 93. It rises in Kordun

Kordun

The Kordun region is a part of central Croatia from the bottom of the Petrova Gora mountain range, which extends along the rivers Korana and Slunjčica, and forms part of the border region to Bosnia and Herzegovina. The southern border of Kordun touches the Lika region...

 west of Slunj

Slunj

Slunj is a town in the mountainous part of Central Croatia, located along the important North-South route to the Adriatic Sea between Karlovac and Plitvice Lakes National Park, on the meeting of the rivers Korana and Slunjčica...

 and flows northwards, in parallel to Dobra and Korana, through Generalski Stol

Generalski Stol

Generalski Stol is a municipality in Karlovac County, Croatia. There are 3,199 inhabitants, 99% of whom are Croats.- Name and history :Generalski Stol played a historically important role in defending Croatia and western Europe by preventing Ottoman incursions further west...

 and Duga Resa

Duga Resa

Duga Resa is a town in Karlovac County, Croatia. It is located east of Rijeka.-Name:The earliest reference to Duga Resa is from the year 1380...

, when it finally flows into the Korana in the south of Karlovac

Karlovac

Karlovac is a city and municipality in central Croatia. The city proper has a population of 49,082, while the municipality has a population of 59,395 inhabitants .Karlovac is the administrative centre of Karlovac County...

 (at Mostanje

Mostanje

Mostanje is a location in Karlovac, Croatia. It is connected by the D1 highway....

/Turanj).

The Gojak Hydroelectric Power Plant

Gojak Hydroelectric Power Plant

Gojak Hydroelectric Power Plant is a hydroelectric power plant on river Dobra, near the town of Ogulin, in Karlovac County, Croatia.The Gojak Hydroelectric Power Plant is a high pressure diversion plant which harnesses the river power of the Ogulinska Dobra and Zagorska Mrežnica rivers.It is...

 is a high pressure diversion plant which harnesses the river power of the Ogulinska Dobra and Mrežnica rivers.