Freestone · Slate · Castilla y León, ES

Río Sil

Río Sil — Cañon del Río Sil desde el mirador de Vilouxe

The Sil dominates the El Bierzo landscape — 80 km of slate-based freestone with outstanding productivity.

Today · Closed season
Frenchie
Forecast · Today
Closed season
Out of season. Try elsewhere.
40% projected
Today's fly
Frenchie
Frenchie
Conditions on the water · Today
Live gauge
Level
Rising
4.82 m
Lifting fast
Water temp5.8°C
ClarityUnfishable
Weather10°C
WindN 12 km/h
Pressure1014 hPa
Rain · recent26.4 mm
Rain · ahead15.1 mm

The nearest gauge doesn't record temperatures, so we've estimated it — defer to the river keeper's advice.

Water temperature for Brown Trout
Cool — slow
6°C est.ideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
Nymphing can work through most of the day.
Where
Cover mixed depths.
Method
Start with tight-line nymphs and adjust if fish rise or drift higher.
Kit
9 ft #4 rod, floating line, 12 ft tapered leader to 4–5 lb fluoro tippet.
Hatch timeline · todayQuiet day

Low insect activity predicted today

Sub-surface · on the nymphunder the surface

Hatch predictions

Top nymph shown — see all 3 guilds as a supporter.

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Evidence
Survey-backed · regionalHigh confidence

Backed by regional invertebrate surveys; no sampling on this exact reach yet.

Through the year
0–3 scale · November highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
1
Large Dark OliveHatch
1
2
2
1
Blue Winged OliveHatch
1
2
2
2
2
1
Autumn OliveHatch
1
2
1
Brown SedgeHatch
1
2
2
2
1

Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.

Ranked for today
Brown Trout fly box
Permits & access
Permit required — see local rules.
  • Castilla y León fishing licence required
  • Many premium trout waters use the Junta's tramo-based management system, including EDE sections, so check the exact section and current rules before travel.
What's coming
Plan ahead
5-day outlook
Fishing better nearby · 5
Río Ser
52 km
30
Brown trout
El Bierzo Tributary Network
9.0 km
0
Brown trout
Río Burbia
19 km
0
Brown trout
Río Selmo
23 km
0
Brown trout
Río Cabrera
28 km
0
Brown trout
Gallery · 2
  1. Río Sil — Cañon del Río Sil desde el mirador de Vilouxe
    Cañon del Río Sil desde el mirador de Vilouxe
  2. Terrain map of the venue
    Terrain map
About this water

Large wild brown populations thrive on slate geology and consistent base flows. Dramatic gorges and productive pools create varied habitat: technical upper reaches with selective fish to larger holding water downstream. Strong mayfly hatches throughout season and 8-hour response time make this a premier fly-fishing destination.

  • Slate
Water quality (WFD)
  • Ecology: Bad
  • Chemical: Unknown
What this classification means

WFD ecological status Poor → Bad corrected to EEA WISE 2022 (3rd RBMP) classification for waterbody ES010MSPFES425MAR000880 (was a stale earlier-cycle value). Source: EEA WISE SWB_SurfaceWaterBody (discodata.eea.europa.eu), verified 2026-06-18.

WFD classification · ES010MSPFES425MAR000880

The full read · show the working · for Brown Trout · confidence 75%
How the 0 is built — score × weight = contribution
Temperature33 × 28%9.2
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time40 × 13%5.2
Pressure80 × 7%5.6
Insect activity28 × 12%3.4
Conditions total= 58
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Warmer water — toward the 10–16 °C ideal band — would lift the temperature score.
The dawn and dusk windows score higher than the midday lull.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout Last Sunday of March → 31 July
Related guides
Pyrenees PlaybookSpanish riversEuro Nymphingsubsurface methods
Booking & contacts
At a glance

Río Sil is a freestone river in Castilla y León, Spain. Its recorded elevation is about 554 m above sea level and the catchment geology is slate. The river is described as roughly 80 km long. The species listed for this water is brown trout. The trout season is recorded as running from Last Sunday of March to 31 July. Best window recorded for anglers: March–July (season); best dry fly May–June. Core methods listed: dry fly; nymph; streamer or wet fly on larger reaches. Level and flow data for this water is linked from 4 gauges. Its Water Framework Directive ecological status is recorded as bad. Nearby waters in our listings include El Bierzo Tributary Network at 9.0 km, Río Burbia at 19 km and Río Selmo at 23 km.