Freestone · Granite · Castilla y León, ES

Río Arlanzón

Río Arlanzón — Río Arlanzón a su paso por Burgos

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.

Tomorrow · Closed season
Pheasant Tail Nymph
Forecast · Tomorrow
Closed season
Out of season. Try elsewhere.
45% projected
Today's fly
Pheasant Tail Nymph
Pheasant Tail Nymph
Conditions on the water · Tomorrow
Live gauge
Level
Rising
0.07 m
Lifting fast
Water temp12.1°C
ClarityUnfishable
Weather17°C
WindN 23 km/h
Pressure1019 hPa
Rain · recent2.8 mm
Rain · ahead0.1 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
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.
Likely species
Mayflies
Stoneflies
Caddisflies
Gammarids
Hatch timeline · tomorrowPeak at 4pm

12pm(now) — Autumn Olive

Stage: On emergersApproach: Emerger or dryActivity: 31%
Also:Daddy Long Legs26%
Peak emergence windowWeather boost8 food groups active

Peak activity at 4pm — Blue Winged Olive (Blue Winged Olive, Weather boost)

Sub-surface · on the nymphunder the surface

Hatch predictions

Supporters see the full sub-surface read.

Start free trial

14-day free trial. Cancel anytime.

Beyond the hatch · worth watchingambient prey(1)

Hatch predictions

Supporters see what else is on the menu.

Start free trial

14-day free trial. Cancel anytime.

Evidence
Survey-backed · regionalHigh confidence

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

Through the year
0–3 scale · September 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 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
0
Brown trout
Río Revinuesa
41 km
0
Brown trout
Upper Río Duero
42 km
Brown trout
Embalse de la Cuerda del Pozo
45 km
Carp · Barbel
Río Ucero
55 km
Brown trout
Gallery · 2
  1. Río Arlanzón — Río Arlanzón a su paso por Burgos
    Río Arlanzón a su paso por Burgos
  2. Terrain map of the venue
    Terrain map
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 0 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow40 × 22%8.8
Clarity95 × 18%17.1
Feeding Time70 × 13%9.1
Pressure80 × 7%5.6
Insect activity52 × 12%6.2
Conditions total= 75
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