Stillwater · Mixed · Mid Wales / Carmarthenshire, GB-WLS

Llyn Brianne

Llyn Brianne Reservoir from the western shore, open water toward the spillway with Tywi Forest on the far hillside.

Llyn Brianne is a great upland reservoir flooded into the headwaters of mid Wales, an acid catchment of peat and rock where the water runs soft and the wild brown trout run hard.

Marginal · Rainbow
Daddy Long Legs · 10–12
A patient day, if you fancy it
Good wave on — drift country. Slow going — pick your moments and do not force it.
44% confidence
limited data

Llyn Brianne is often best in spring through autumn.

What moved it
  • WindN 12 km/hLight breeze
Today's fly
Daddy Long Legs
Daddy Long Legs10–12
Upstream dry, on top
Conditions on the water
Estimate
Wind
Light breeze
N 12 km/h
N
N
from the north
Wave20 cm ripple
Water temp6.8°C
Air temp0°C
CloudClear
Pressure1014 hPa
Rain · recent0.0 mm

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

How to fish it · for Rainbow
When
No strong hatch signals at the moment — general searching tactics should work best. The ripple is helpful — fish should move onto the feed and a slow-drifted team or single wet will cover water well.
Where
Set up a broadside drift and cover the water systematically. Work a bushy searching pattern on the bob and drop a contrasting nymph on the point.
The plan
Plan A

Set up a broadside drift and cover the water systematically. Work a bushy searching pattern on the bob and drop a contrasting nymph on the point.

Plan B

If the main plan is not working, switch to a smaller, more imitative pattern fished slower and deeper. A change of drift angle can also make a difference.

Watch for

Keep an eye on changing conditions — wind shifts and cloud breaks can trigger short feeding spells.

Boat — drift

A gentle ripple is ideal for drifting — broadside drift covering the wind lanes should be productive.

Sub-surface · on the nymphunder the surface

Hatch predictions

Top nymph shown — see all 2 guilds as a supporter.

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Beyond the hatch · worth watchingambient prey(1)

Hatch predictions

Top prey shown — see all 4 as a supporter.

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Through the year
0–3 scale · November highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Heather FlyHatch
2
2
Daddy Long LegsHatch
2
3
3
2
Claret DunHatch
2
3
2
Murrough (Great Red Sedge)Hatch
2
3
2

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

Buzzer team todayfor the conditions now
Point
Bloodworm
Not in this water's box
#10
How to fish it
Slow-sink line · slow figure-of-eight, pausing to let the flies hang

Fly recommendations

Point fly shown — supporters see the whole team, sizes and why.

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Ranked for today
Rainbow fly box

Traditional wild-trout llyn fishing. Wet flies and dabblers stay central, with buzzer, caddis, terrestrials and occasional small fry patterns becoming important as the season warms.

BU
Bumble
10–12 · Pattern
Fish it in the film
What's coming
Plan ahead
5-day outlook
Condition match
66%
Cloud25%
Wind100%
Temp60%

A reasonable day here, though cloud isn't quite in the sweet spot.

Other water nearby · 5
Llyn Berwyn
9.0 km
Brown trout
Llyn Carw
11 km
Brown trout
Llyn Gynon
14 km
Brown trout
Llyn Egnant
16 km
Brown trout
Llyn Hir
17 km
Brown trout
Gallery · 5
  1. Llyn Brianne Reservoir from the western shore, open water toward the spillway with Tywi Forest on the far hillside.
    Llyn Brianne Reservoir
  2. View across the Afon Tywi arm of Llyn Brianne toward the dense Tywi Forest on the far shore.
    Llyn Brianne — the Tywi arm
  3. Broad landscape view of Llyn Brianne Reservoir looking north, open water in the foreground and moorland and woodland rising around.
    Llyn Brianne Reservoir
  4. Wide panoramic view of Llyn Brianne reservoir on a clear day, forested hills descending to the water.
    Llyn Brianne panorama
  5. Terrain map of the venue
    Terrain map
About this water

This is not a manicured day-ticket pond. It's a big, weather-beaten upland water where the fish are mostly small, dark, beautifully marked and entirely uninterested in being caught easily. The browns are wild and earn their living in lean water, with stocked fish added over the years to the mix. The reward isn't size, it's the place — bare hills, drifting cloud, and trout that have never seen anything soft in their lives. Fish a team of traditional Welsh wets across the wave from drifting boat or rocky bank, and on the right blustery day the offers come fast and savage. On the wrong day the wind simply wins.

  • Lake
  • Mixed
Why this score
  • Wind conditions (ripple) closely match what this water fishes best in.
Related guides
Thermal Layers & Troutreading depth and temperatureEuro Nymphingsubsurface methods
Casting instructors near here
Booking & contacts
Boards & regulators
At a glance

Llyn Brianne is a lake in Mid Wales / Carmarthenshire. It sits at about 276 m above sea level. Our data lists rainbow trout and brown trout here. Core methods listed: Top-dropper bob fly tripped through the surface; Dry fly to rising fish on calmer evenings. Nearby waters in our listings include Llyn Berwyn at 9.0 km, Llyn Carw at 11 km and Llyn Gynon at 14 km.