Fly Fishing in Europe – Slovenia: The Marble Trout Religion

This superb relative of the brown trout is only found in streams draining into the Adriatic Sea. I was lucky to meet Branko Gasparin in the 90’s at the time when he had just left the restaurant he led masterfully with his brother and their respective wives to create in Most Na Soci a lodge totally dedicated to fly-fishing: Vila Noblesa!

Like an addiction…
The mysterious Marble trout is estimated to be only native to rivers of the Adriatic river system. Catching a huge one with a fly is possible in Slovenia, a small eastern European country bordered by Italy to the west and Austria to the North.

After several fly fishing trips in this beautiful country of clear rivers and with this incredible guide, I have learnt a lot about the marble trout and its particular behavior in the Slovenian rivers. To understand Branko’s passion (a kind of religion) for this trout, we need to know more about his country and its rivers as they have strongly influenced and directed the way he sees the fly-fishing for the biggest specimen.

emerald_river_134301648.jpgBranko lives in the small village of Most Na Soci and can fish both the Soca and its tributaries (Lepena, Koritnica, Tolminka) and the Idrijca (his river). All these waters are gin clear and flow over white gravel where sight-fishing with a dry fly, a nymph, or a streamer is a delicate pleasure! Branko Gasparin is known worldwide for his amazing tying patterns and fishing techniques because he is constantly looking for new products.

The marble trout is fascinating for a fly angler and I can say that Branko has spent most of his time analyzing the biggest ones to increase his catching rates! In the Soca River the growth of marble trout is very fast because of the richness of the environment. Some scientist studies have shown that a marble trout could reach 60 cm in just four years which is amazing compared to other European rivers. According to my experience, I can say that it is easier to catch one of these monsters if you don’t consider it as a trout but as a pike! No it is not a joke! Marble trout live under boulders and will follow a fly right up to your waders before gulping it in. You will have to strike hard and fast once the trout takes the fly, as these fish can spit the fly quickly and not come back for a second look. In the Soca river some trophy size “marmorata” are toothy eating machines, seeking targets (small grayling and trout) like a missile.

big_streamers_big_trout_406618609.jpgSince my first trip in Slovenia, I have always been dedicated to the admiration of the Idrijca river, probably because it is easier to spot a very large active marble trout even during the day. The best hours are usually between 11 and 2 o’clock, and then their sight-fishing becomes more difficult.

The method that works is quite simple if you have the chance to locate one of these monsters. Try to position yourself on a promontory (a big stone will do the job!). Always chose a strategic place to attack the fish, either with a big nymph (size 2-4) or with any of some highly weighted Slovenian sculpin imitations tied on a large jig hook. If you spend every day on the water casting tiny dry flies, you might have a lot of action but your chances of hooking a trout of a lifetime are slim to none. Monster marble trout eat sculpins, crayfish, big stoneflies and most of the time small grayling.

I fish many big streamers from my own tying or from Branko’s and I can tell you that it works. Casting these flies will make your arm fall off at the end of the day, but throw them often enough and some good things will happen! I have also noticed that these big marble trout prefer to eat under low light conditions. Since they are often eating large meals they often go long periods without feeding while they digest their last victim.

21_kg_marble_trout_158870532.jpgOn the Idrijca river a good cloud cover and especially rain will often trigger intense feeding in the middle of the day. In Slovenia, only fly-fishing is allowed and my friend Branko often uses a 10 weight rod for giant fish! Some anglers will say that landing monstrously large trout is not always the main priority, but admit that they would not mind a nice picture of a large and splendid marble trout on the desk of their office! It is time to convert to a new religion…

My tackle checklist for the monsters:

Rods: TFO Ticrx 9’ #8 (4 pieces), AIRFLO Blue Tooth 9’ #10 (4 pieces).
Reels: Airflo Airlite 9/10.
Backing: Gel Spun 30 and 50lbs 300 yards.
Lines: Airflo Ridge supple impact, Airflo Six Sense DI8, Airflo Depth finder 30’ head 300 and 400 grain.
Leaders: Airflo ten feet trout Polyleaders sets.
Nymphs: Hare and Copper, Hare’s Ear, Stoneflies, Pheasant Tail.
Streamers: Deceivers, minnow patterns, Sculpin patterns, fry and leeches patterns.


If you fancy a week or two in Slovenia, contact Selectour Voyages OVP Agency, Galerie Marchande Carrefour, 71680 Crèches sur Saône France.
Alexandre Ecochard 00 33 (0)3 85 37 41 70

Email :


Laurent Guillermin

Laurent Guillermin is a French reporter and photographer. Laurent’s images and articles have appeared in a great number of fishing magazines in France and Europe. He’s also well-known in the small fly tying “world” and has commercial patterns tied by Easy Fly. He has traveled all over the world as a reporter and is considered as an expert fly fisher for trout, grayling, pike, carp, sea bass, bonefish and permit. “Every time you go out fishing you can have a different experience. That’s what it’s all about!”

You can contact him on


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