Updated
Llyn Cwellyn (Llyn Quellyn in some antiquated texts) is a reservoir in North Wales which supplies drinking water to parts of Gwynedd and Anglesey. It lies on Afon Gwyrfai in Nant y Betws between Moel Eilio and Mynydd Mawr in the northern part of Snowdonia National Park. It has an area of 215 acres (0.87 km2), and is over 120 ft (37 m) deep.
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Weather at Llyn Cwellyn
43°F, Fog · H 49° / L 40° · 88% chance of rain3-day forecast
H: 49° L: 40°
Fog
43°
|
Feels like 39°
Precipitation
88%
Humidity
98%
Wind
3 mph
UV Index
0
Weather notes:
🌧️Rain expected
12 AM
47°
3 AM
46°
6 AM
48°
9 AM
46°
12 PM
42°
3 PM
41°
6 PM
43°
9 PM
49°
Frequently asked questions
- Where is Llyn Cwellyn?
- Llyn Cwellyn is a reservoir in Wales.
- Can you swim at Llyn Cwellyn?
- There is no fixed answer for Llyn Cwellyn: whether it is safe to swim there on a given day depends on the water temperature, recent rainfall, and any advisories posted at Llyn Cwellyn in Wales. Check current water conditions before you go, and follow posted signs and local guidance.
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Location & Contact
Wales
🏞️ Best times & visiting tips
- ›Check for boat launch facilities and fees
- ›Obtain required fishing licenses before arrival
- ›Be aware of lake-specific regulations and restrictions
- ›Monitor water quality reports before swimming
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