Freestone · Limestone · Andalucía / Jaén (Sierra de Cazorla–Las Villas)

Guadalquivir (upper / Cazorla headwaters)

Clear spring water cascading over moss-covered rock at the source of the Guadalquivir river in the Sierra de Cazorla natural park
Contributor photo

The source of the Guadalquivir, Sierra de Cazorla

Edmundo Sáez

This is the Cazorla headwater stretch of the Guadalquivir, rising in the Sierra de Cazorla y Las Villas.

Marginal · Brown Trout
Foam Beetle · 14-18
Marginallive now
Slow going — pick your moments
River temperature is the limiting factor today, not the flow. Fish dawn or dusk if you go at all, and handle everything with extra care.
80% confidence
What moved it
  • LevelDry recentlyNo gauge reading
  • Water temp19.8°C
  • ClarityClear
Today’s fly
Foam Beetle
Foam Beetle14-18
Proven pattern for this period
Conditions on the water
Estimate
Level
Dry recently
No gauge reading
Water temp19.8°C
ClarityClear
Weather21°C
WindSE 3 km/h
Pressure1019 hPa
Rain · recent0.0 mm
Rain · ahead0.0 mm

No gauge on this water — readings are regional estimates from weather, not a live gauge.

Water temperature for brown trout
Warm — slow
20°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.
Why this works
⚠️ Water at 19.8°C — above the brown trout caution line (18°C). Fish dawn or dusk only. Land it fast, wet hands, no air shots. Otherwise poor — water clarity is in the right range.
Hatch timeline · todayQuiet day

Hatch predictions

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Sub-surface · on the nymphunder the surface

Hatch predictions

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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
Records-basedModerate confidence

Based on species-occurrence records, not local invertebrate surveys.

Through the year
0–3 scale · July highlighted
J
F
M
A
M
J
J
A
S
O
N
D
GrannomHatch
2
2
Evening SedgeHatch
2
3
3
3
2
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
1
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.
  • Junta de Andalucía licence plus trout surcharge required
  • Upper Guadalquivir cotos and managed beats can carry their own allocation and method rules, so confirm the current BOJA order and local permit conditions before travel.
What's coming
Plan ahead
5-day outlook
Cooler water nearby · 3
Water here around 20°C — probably warm enough to stress brown trout. These are likely cooler.
Río Castril
26 km
~17°C
Brown trout
Río Madera (Bajo)
31 km
~17°C
Brown trout
Río Borosa
7.0 km
~18°C
Brown trout
Gallery · 2
  1. Clear spring water cascading over moss-covered rock at the source of the Guadalquivir river in the Sierra de Cazorla natural park
    The source of the Guadalquivir, Sierra de Cazorla
  2. Terrain map of the venue
    Terrain map
About this water

This is the Cazorla headwater stretch of the Guadalquivir, rising in the Sierra de Cazorla y Las Villas. Here the river is still a limestone mountain trout stream: native brown trout of the distinct Mediterranean lineage (trucha común andaluza), protected under catch-and-release rules since 2005, share the water with some managed rainbow beats further through the wider upper system. Clear, quick-clearing limestone flows reward a careful, low-water approach and technical presentation.

  • Limestone
Water quality (WFD)
  • Ecology: Moderate
  • Chemical: Unknown
What this classification means

WFD ecological status Poor → Moderate corrected to EEA WISE 2022 (3rd RBMP) classification for waterbody ES050MSPF011009044 (was a stale earlier-cycle value). Source: EEA WISE SWB_SurfaceWaterBody (discodata.eea.europa.eu), verified 2026-06-18.

WFD classification · ES050MSPF011009044

The full read · show the working · for brown trout · confidence 80%
How the 29 is built — score × weight = contribution
Temperature28 × 28%7.8
Flow60 × 22%13.2
Clarity95 × 18%17.1
Feeding Time40 × 13%5.2
Pressure80 × 7%5.6
Insect activity50 × 12%6.0
Conditions total= 55
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
The dawn and dusk windows score higher than the midday lull.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Troutdurante los periodos hábiles (check current BOJA) → during the designated open period
Related guides
Pyrenees PlaybookSpanish riversEuro Nymphingsubsurface methods
Booking & contacts