Glacial llyn beneath the Black Mountain escarpment in the western Brecon Beacons. Wild brown trout. Spectacular setting below the Lady of the Lake cliff. Access from Llanddeusant — 3-mile walk. Small, wild fish on traditional methods.
- Lake
- Sandstone
Head to
Wind driftSE wind
North-western end
A southeasterly has held for most of a day at much the same temperature as the 11°C water. No thermal steer either way, but the drift still stacks food against the north-western end — the bank it is blowing into — so start there. This reads the upper water, though — a bottom bait at range feels it far less than a floater or a fish in the margins. Treat it as a tiebreaker between good swims rather than an override — features and angling pressure usually count for more.
How to fish it · for Trout
When
June to August
Where
Work a bushy searching pattern on the bob and drop a contrasting nymph on the point.
The plan
Plan A
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
Sedge should come on through the afternoon as the water warms.
Bank
Bank-only venue. Fish from accessible margins, points, weed edges, and inflows.
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 3 guilds as a supporter.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey(1)
Hatch predictions
Top prey shown — see all 4 as a supporter.
Start free trial14-day free trial. Cancel anytime.
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
2
2
1
Heather FlyHatch
2
2
Daddy Long LegsHatch
2
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.
Ranked for today
Trout fly box
More straightforward stocked-water behaviour than the upland competition reservoirs, with stronger early-season lure and booby bias but still good natural-fly periods.
What's coming
Plan ahead
5-day outlook
Condition match
51%
Cloud70%
Wind30%
Temp60%
A reasonable day here, though wind isn't quite in the sweet spot.
Other water nearby · 5
Gallery · 2
Terrain map
About this water
Why this score
- Wind conditions (windy) are not ideal for this water.
- Buzzer is in its seasonal window, boosting the chance of targeted feeding.
Directions
Seasons & zones
- Trout 3 March → 30 September
Related guides
Casting instructors near here
Booking & contacts
Permits & access
- Fishing Passport / local Welsh llyn networkFor Llyn y Fan Fach, treat it as a wild-llyn access water rather than a commercial fishery. Start with Fishing Passport and Fishing in Wales guidance, then narrow to the controlling club if needed.
- Fishing in Wales llyn guideRules and access info for Llyn y Fan Fach
Boards & regulators
Llyn y Fan Fach
Glacial llyn beneath the Black Mountain escarpment in the western Brecon Beacons.
Head to
Wind driftSE wind
North-western end
A southeasterly has held for most of a day at much the same temperature as the 11°C water. No thermal steer either way, but the drift still stacks food against the north-western end — the bank it is blowing into — so start there. This reads the upper water, though — a bottom bait at range feels it far less than a floater or a fish in the margins. Treat it as a tiebreaker between good swims rather than an override — features and angling pressure usually count for more.
How to fish it · for Trout
When
June to August
Where
Work a bushy searching pattern on the bob and drop a contrasting nymph on the point.
The plan
Plan A
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
Sedge should come on through the afternoon as the water warms.
Bank
Bank-only venue. Fish from accessible margins, points, weed edges, and inflows.
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 3 guilds as a supporter.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey(1)
Hatch predictions
Top prey shown — see all 4 as a supporter.
Start free trial14-day free trial. Cancel anytime.
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
2
2
1
Heather FlyHatch
2
2
Daddy Long LegsHatch
2
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.
Ranked for today
Trout fly box
More straightforward stocked-water behaviour than the upland competition reservoirs, with stronger early-season lure and booby bias but still good natural-fly periods.
What's coming
Plan ahead
5-day outlook
Condition match
51%
Cloud70%
Wind30%
Temp60%
A reasonable day here, though wind isn't quite in the sweet spot.
Other water nearby · 5
Gallery · 2
Terrain map
About this water
Glacial llyn beneath the Black Mountain escarpment in the western Brecon Beacons. Wild brown trout. Spectacular setting below the Lady of the Lake cliff. Access from Llanddeusant — 3-mile walk. Small, wild fish on traditional methods.
- Lake
- Sandstone
Why this score
- Wind conditions (windy) are not ideal for this water.
- Buzzer is in its seasonal window, boosting the chance of targeted feeding.
Directions
Seasons & zones
- Trout 3 March → 30 September
Related guides
Casting instructors near here
Booking & contacts
Permits & access
- Fishing Passport / local Welsh llyn networkFor Llyn y Fan Fach, treat it as a wild-llyn access water rather than a commercial fishery. Start with Fishing Passport and Fishing in Wales guidance, then narrow to the controlling club if needed.
- Fishing in Wales llyn guideRules and access info for Llyn y Fan Fach
Boards & regulators