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
How to fish it · for Trout
When
June to August
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
Evening tends to be the best period in summer — stay late if you can for a sedge or spinner fall.
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 2 guilds with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 5 with Pro.
Start free trial14-day free trial. Cancel anytime.
Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
1
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
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
79%
Cloud70%
Wind100%
Temp60%
A good match for Llyn y Fan Fach — most conditions are close to what it fishes best in.
Other water nearby · 5
Gallery · 1
Terrain map
About this water
Why this score
- Wind conditions (ripple) closely match what this water fishes best in.
- Daddy longlegs are in their seasonal window, boosting the chance of targeted feeding.
Directions
Seasons & zones
- Trout 3 March → 30 September
Related guides
Casting instructors near here
Booking & contacts
Clubs & associations
Llyn y Fan Fach
Glacial llyn beneath the Black Mountain escarpment in the western Brecon Beacons.
How to fish it · for Trout
When
June to August
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
Evening tends to be the best period in summer — stay late if you can for a sedge or spinner fall.
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 2 guilds with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 5 with Pro.
Start free trial14-day free trial. Cancel anytime.
Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
1
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
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
79%
Cloud70%
Wind100%
Temp60%
A good match for Llyn y Fan Fach — most conditions are close to what it fishes best in.
Other water nearby · 5
Gallery · 1
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 (ripple) closely match what this water fishes best in.
- Daddy longlegs are in their seasonal window, boosting the chance of targeted feeding.
Directions
Seasons & zones
- Trout 3 March → 30 September
Related guides
Casting instructors near here
Booking & contacts
Clubs & associations