Stillwater · Ordovician Volcanic · Wales / Snowdonia (Blaenau Ffestiniog uplands)

Llyn Conglog

Llyn Conglog terrain map
Terrain map

Conglog sits high and alone in the moorland above Blaenau Ffestiniog, the kind of water you earn with a proper walk before you ever wet a line.

Marginal · Trout
Diawl Bach · 12-14
A patient day, if you fancy it
Water temperature is the limiting factor today, not the wave. Fish dawn or dusk if you go at all, and handle everything with extra care.
42% confidence
limited data
What moved it
  • WindS 7 km/hLight breeze
Today’s fly
Diawl Bach
Diawl Bach12-14
Washing-line, sub-surface
Conditions on the water
Live gauge
Wind
Light breeze
S 7 km/h
N
S
from the south
WaveRipple
Water temp
Air temp30°C
CloudClear
Pressure1019 hPa
Rain · recent0.0 mm

Some readings unavailable — check directly before fishing.

How to fish it · for trout
When
June–August; best on overcast, breezy days
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. Keep a sedge-style dry or emerger on a short leader for the evening rise.
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. Keep a sedge-style dry or emerger on a short leader for the evening rise.

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

Watch for Sedge towards evening — this could be the best window of the day.

Boat — drift

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

Through the year
0–3 scale · July highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Daddy Long LegsHatch
2
3
2
Murrough (Great Red Sedge)Hatch
2
3
2
Black MidgeHatch
2
3
3
3
3
3
3
3
3
3
3
2
Lake OliveHatch
1
2
2
2
2
2
1

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

Ranked for today
Trout fly box
Bays & launches · 1
Day ticket via Cambrian Angling AssociationAccess varies
Remote wild brown trout llyn high above Blaenau Ffestiniog, reached on foot; covered by the Cambrian AA's single day ticket across the whole llyn portfolio.
What's coming
Plan ahead
5-day outlook
Condition match
55%
Cloud25%
Wind100%
Temp25%

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

Other water nearby · 5
About this water

Conglog sits high and alone in the moorland above Blaenau Ffestiniog, the kind of water you earn with a proper walk before you ever wet a line. Eight-odd acres of dark upland water holding a modest population of wild brown trout that have never seen a stocking truck and don't much care for a bright afternoon. Bring a spare fly box and low expectations on the weather — cloud cover and a ripple make the difference between a slow afternoon and a good one. It's not a lake that rewards impatience, but the ones that come out are entirely your own, in the honest sense that matters up here.

  • Lake
  • Ordovician volcanic
Why this score
  • Wind conditions (ripple) closely match what this water fishes best in.
  • High temperatures may push fish deeper and reduce surface activity.
  • Damsel Nymph is in its seasonal window, boosting the chance of targeted feeding.
Related guides
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