Freestone · Granite · Castilla y León

Río Arlanzón

Río Arlanzón terrain map
Terrain map

The Arlanzón rises in the Sierra de la Demanda above Pineda de la Sierra and runs down through the upper valley before feeding the Burgos plain.

Good · Brown Trout
Klinkhammer · 14-18
Goodlive now
A proper day on the water
Low and clear — careful approach country. Stay small, stay accurate.
75% confidence
What moved it
  • Level0.12 m
  • Water temp12.4°C
  • ClarityClear
Today’s fly
Klinkhammer
Klinkhammer14-18
High-confidence seasonal pick
Conditions on the water
Live gauge
Level
Steady
0.12 m
Water temp12.4°C
ClarityClear
Weather12°C
WindNE 15 km/h
Pressure1025 hPa
Rain · recent0.0 mm
Rain · ahead0.0 mm

Live readings — water temperature is an estimate where the gauge does not record it.

Water temperature for brown trout
Ideal
12°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
Good — water temperature is working for you, but insect activity is the limiting factor today.
Hatch timeline · todayQuiet day

Hatch predictions

Today's headline hatch shown — see all 10 active hatches hour by hour 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
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
  • Pineda-area cotos require tramo permits
  • Sierra de la Demanda altitude means the season effectively starts later than the calendar opener.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Río Arlanza
16 km
80
Brown trout
Río Revinuesa
41 km
Brown trout
Upper Río Duero
42 km
80
Brown trout
Embalse de la Cuerda del Pozo
43 km
Carp · Barbel
Río Ucero
55 km
Brown trout
About this water

The Arlanzón rises in the Sierra de la Demanda above Pineda de la Sierra and runs down through the upper valley before feeding the Burgos plain. The upper basin around Pineda is a well-managed Burgos trout system with established coto structure, fly-only/catch-and-release periods, and reliable mountain-water character. Strong granite headwaters; pair with the SAIH Duero EA508 gauge at Pineda de la Sierra for live conditions.

  • Granite
The full read · show the working · for brown trout · confidence 75%
How the 78 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time40 × 13%5.2
Pressure80 × 7%5.6
Insect activity38 × 12%4.6
Conditions total= 78
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
What would change the calculation
The dawn and dusk windows score higher than the midday lull.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • TroutLast Sunday of March → 31 July
Related guides
Pyrenees PlaybookSpanish riversEuro Nymphingsubsurface methods
Booking & contacts