Location
The river flows through the Lika region of Croatia for approximately 11 km. The river originates at Majerovo Vrelo, situated at 465 metres above sea level. This area lies within the Central European Time zone (GMT+2).
Spring
The spring of the Gacka River, called Majerovo Vrelo, is located at an elevation of 465 metres above sea level.
Characteristics
The Gacka River is a chalk stream, 10–20 metres wide, with a depth ranging from 1 to 4 metres. Its total length is approximately 11 km.
Description
The Gacka River is a world-famous trout fishing destination, celebrated for its clear waters, abundant insect life, and easy casting conditions.
The river originates from several spring-fed lakes, most notably Tonkovića Vrilo and Majerovo Vrilo, which are surrounded by charming traditional water mills. Once 32 km long, the Gacka’s course was shortened to 11 km after a hydroelectric plant was built in 1960, making it one of the world’s longest sinking rivers.
Flowing gently through a flat, marshy valley bordered by rocky hills, the Gacka is a classic chalk stream. Its clean, oxygen-rich waters and nutrient-rich muddy bottom support lush aquatic vegetation and a thriving insect population, creating ideal conditions for trout. With mostly open banks free of tall vegetation, even novice anglers can enjoy effortless casting along this scenic river.
Fish Species
The Gacka River is world-renowned for its brown trout (Salmo trutta), making it a prime destination for passionate fly fishermen. Thanks to the river’s clean, oxygen-rich waters and abundant natural food, brown trout here grow faster than in most other rivers, with trophy specimens sometimes reaching 4–5 kg.
Rainbow trout (Oncorhynchus mykiss) are also found in the river and can grow even larger, providing exciting challenges for anglers. While less common, grayling (Thymallus thymallus) is occasionally spotted in the Gacka, adding to the river’s diversity.
These species, along with the river’s pristine conditions, make the Gacka a true haven for fly fishing, especially for those seeking large, healthy trout in a scenic setting.
Type of fishing & equipment
The Gacka River is perfect for practicing a variety of fly-fishing techniques, primarily targeting brown trout and rainbow trout. Dry fly fishing is highly effective during insect hatches, while nymphing produces consistent results throughout the river. Streamer fishing can also be used to target larger trout in deeper pools and slower sections.
When you book a trip with us, we provide a detailed overview of the most effective fishing methods and strategies for the Gacka, along with recommendations for rods, lines, flies, and all essential equipment to ensure a successful and enjoyable angling experience.
Season and regulations
Fishing on the Gacka River is primarily focused on fly-fishing, with artificial flies recommended throughout most of the river. In designated areas, catch-and-release is encouraged to help preserve the healthy trout populations. In the river’s lower sections and surrounding lakes, other artificial lures and, in some cases, natural bait are permitted, provided that all local fishing regulations are followed.
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Beyond fishing
The Gacka River is ideally located for exploring some of Croatia’s most stunning natural and cultural sites. It lies close to Sjeverni Velebit National Park, Plitvice Lakes National Park, and the Adriatic coast, making it easy to combine fly-fishing with sightseeing.
The Gacka Valley is also rich in historical heritage. Evidence of human habitation dates back to the Middle Stone Age, discovered in Pećina Cave. Early Illyrian artifacts have been found in Bezdanjača Cave near Vrhovine, which contains one of the largest cave necropolises in Europe.
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