Slo-Fly.

Lesly “Lesko” Janssen is the heart and soul behind Slo-Fly, based in Tolmin, Slovenia. Originally from the Netherlands, he fell in love with the rivers of the Soča Valley more than 20 years ago and never left. Known for his enthusiasm, patience, and sharp sense of humor, Lesly makes every guided trip feel like a day spent with a friend who just happens to know all the secret spots. When he’s not guiding, he’s tying flies, inventing new fishing tools, or exploring hidden canyons in search of marble trout.
Unlike many guides who focus on the most popular sections of the Soča, Lesly prefers to avoid the easily accessible and often crowded stretches. Instead, he takes his guests to quieter waters where solitude, scenery, and wild fish combine for a truly special experience.

Waters & Clubs.

Lesly guides across several fishing districts in the Soča Valley, each offering a different kind of experience:

ZZRS (Fisheries Research Institute waters) – These are generally the easiest waters to fish, making them a great choice for beginners or those looking for a more relaxed day on the river.
RD Tolmin – Lesly’s home waters and where he spends most of his time. These rivers, including the Soča, Idrijca, Bača, and Tolminka, offer more challenging fishing conditions with a mix of technical pools and strong wild fish.
RD Idrija – Known for some of the toughest waters in Slovenia, the Idrijca and its tributaries demand precise presentation, patience, and skill. For experienced anglers seeking a true challenge, this is the ultimate test.