Freestone · Granite · Castilla y León, ES

Río Eresma

Río Eresma terrain map

The Eresma rises in the Sierra de Guadarrama at Valsaín — the upper river through La Granja and into Segovia city is genuine wild-trout water, with strong granite-headwater character and excellent clarity.

Poor · Brown Trout
Klinkhammer · 14-18
Closed season
Out of season. Plenty of other water available now.
Closed — confidence not applicable today.
What moved it
  • Level0.48 mLast reading 5h ago
  • Water temp17.3°C
  • ClarityClear
Today's fly
Klinkhammer
Klinkhammer14-18
High-confidence seasonal pick
Conditions on the water
Live gauge
Level
Steady
0.48 m
Last reading 5h ago
Water temp17.3°C
ClarityClear
Weather18°C
WindE 6 km/h
Pressure1016 hPa
Rain · recent0.1 mm
Rain · ahead8.4 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
Warm — slow
17°C est.ideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
Through the Castilla y León trout season — 3rd Sunday of March to 31 July. Spring olives April through May; summer sedges in evening hours; sin muerte stretches extend through autumn.
Where
Pool tails, riffle heads, and the seams behind boulders through the Segovian beats. The Eresma runs from the Sierra de Guadarrama through clear granite pocket water.
Method
Upstream dry to risers; dry-dropper through the riffles. The water reads clear — long leader, fine tippet, careful approach.
Kit
9 ft #4 — Castilian default. Floating line, 12 ft leader to 4 lb fluoro. Studded boots — granite cobble runs slick.
Hatch timeline · todayPeak at 6am

Hatch predictions

Today's headline hatch shown — see all 8 active hatches hour by hour with Pro.

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Beyond the hatch · worth watchingambient prey

Hatch predictions

Top prey shown — see all 2 with Pro.

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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 · August 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
GrannomHatch
1
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 licence required
  • The Valsaín–La Granja stretch is the wild-trout identity of the river; lower city/agricultural beats follow different (often stocked) management
  • Match the tramo to your goal before booking.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Río Lozoya (cotos & tramos)
14 km
0
Brown trout
Molino de la Horcajada (Lozoya coto)
26 km
0
Brown trout
Río Cega
31 km
0
Brown trout
Upper Río Manzanares (La Pedriza)
16 km
Brown trout
Río Moros
23 km
Brown trout
About this water

The Eresma rises in the Sierra de Guadarrama at Valsaín — the upper river through La Granja and into Segovia city is genuine wild-trout water, with strong granite-headwater character and excellent clarity. Lower reaches downstream of Segovia city become more mixed: stocked beats, urban influence, and warmer summer flow mean the Eresma's fly-fishing identity sits firmly in the upper basin around Valsaín / La Granja, not in the broader river.

  • Granite
The full read · show the working · for Brown Trout · confidence 90%
How the 0 is built — score × weight = contribution
Temperature70 × 28%19.6
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time70 × 13%9.1
Pressure80 × 7%5.6
Insect activity65 × 12%7.8
Conditions total= 77
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout Last Sunday of March → 31 July
Related guides
Pyrenees PlaybookSpanish riversEuro Nymphingsubsurface methods
Booking & contacts