List of lakes of Wales facts for kids
Welcome to a guide about the amazing lakes in Wales! Most lakes here have names that start with "Llyn", which is the Welsh word for "lake". You'll find many beautiful lakes, some natural and some created by people as reservoirs to store water.
Wales' Biggest Lakes by Size
Let's look at the ten largest lakes in Wales based on their surface area. This means how much space they cover on the ground.
- Bala Lake (Llyn Tegid) — about 4.84 square kilometers (1196 acres)
- Llyn Trawsfynydd — about 4.77 square kilometers (1180 acres)
- Lake Vyrnwy — about 4.53 square kilometers (1120 acres)
- Llyn Brenig — about 3.62 square kilometers (894 acres)
- Llyn Celyn — about 3.24 square kilometers (800 acres)
- Llyn Alaw — about 3.08 square kilometers (762 acres)
- Claerwen Reservoir — about 2.65 square kilometers (655 acres)
- Clywedog Reservoir — about 2.43 square kilometers (601 acres)
- Nant-y-moch Reservoir — about 2.12 square kilometers (525 acres)
- Caban Coch Reservoir — about 2.10 square kilometers (519 acres)
Most of these large lakes are actually reservoirs. This means they were made by building dams to hold back water. Bala Lake is special because it's the largest natural lake in Wales. Even though it's natural, its water level has been controlled by special gates since the early 1800s. The biggest natural lake in South Wales is Llangorse Lake. It's also the second largest natural lake in all of Wales!
Lakes in Different Areas of Wales
Wales is divided into different areas called counties and county boroughs. Many lakes are found across these areas. This list includes lakes bigger than 5 acres (about 2 hectares). We're not including small ponds at industrial sites or drinking water storage tanks.
Sometimes, a lake might be so big that it crosses the border between two areas. If that happens, you'll see a little star (*) next to its name.
Anglesey's Lakes
Anglesey is an island off the northwest coast of Wales. It has several interesting lakes.
| Lake name | Main River | Location | Size (acres) | What it's used for |
|---|---|---|---|---|
| Llyn Alaw | River Alaw | SH375853 | 762 | Supplies water to north Anglesey |
| Llyn Coron | No main river | SH380700 | 69 | |
| Llyn Llywenan | No main river | SH347815 | The biggest natural lake on Anglesey | |
| Llyn Penrhyn | No main river | SH313770 | 55 | A bird reserve (RSPB) |
Bridgend's Lakes
Bridgend is in South Wales and has a few notable lakes.
| Lake name | Main River | Location | Size (acres) | What it's used for |
|---|---|---|---|---|
| Kenfig Pool | River Kenfig | SS797815 | 70 | A natural lake |
Cardiff's Lakes
Cardiff, the capital city of Wales, also has lakes within its area.
| Lake name | Main River | Location | Size (acres) | What it's used for |
|---|---|---|---|---|
| Cardiff Bay | River Taff/River Ely | ST190726 | 500 | Used for fun activities and recreation |
| Llanishen Reservoir | Rhymney River | ST185815 | 59 | Supplies water to Cardiff |
| Roath lake | Rhymney River | ST184795 | 30 | Used for fun activities and recreation |
Carmarthenshire's Lakes
Carmarthenshire is a large county in Southwest Wales with various lakes.
| Lake name | Main River | Location | Size (acres) | What it's used for |
|---|---|---|---|---|
| Llyn Brianne | River Tywi | SN790485 | 530 | A reservoir that helps control river flow |
| Llyn y Fan Fach | River Tywi | SN803219 | 25 | A natural lake |
| Lower Talley Lake | Afon Cothi | SN633331 | 62 | A natural lake |
| Usk Reservoir | River Usk | SN832288 | Supplies water |
Gwynedd's Lakes
Gwynedd is a county in northwest Wales, home to many beautiful lakes, especially in the Snowdonia area.
| Lake name | Main River | Location | Size (acres) | What it's used for |
|---|---|---|---|---|
| Llyn Arenig Fawr | River Dee | SH846380 | 84 | A natural lake, supplies water to Bala town |
| Llyn Celyn | River Dee | SH860405 | 815 | Helps control river flow |
| Llyn Cwellyn | Afon Gwyrfai | SH559549 | 215 | A natural lake, supplies water |
| Llyn Dinas | River Glaslyn | SH616495 | 60 | A natural lake |
| Llyn Gwynant | River Glaslyn | SH644519 | 85 | |
| Llyn Idwal | River Ogwen | SH645596 | 28 | |
| Llyn Llydaw | River Glaslyn | SH629543 | 110 | |
| Llyn Mwyngil (Talyllyn Lake) | River Dysynni | SH717099 | 220 | |
| Llyn Padarn | River Seiont | SH572613 | 280 | A natural lake used for fun activities |
| Bala Lake (Llyn Tegid) | River Dee | SH911338 | 1,196 | The largest natural lake in Wales |
| Llyn Trawsfynydd | River Dwyryd | SH674377 | 1,180 | Used for nuclear power (in the past) and hydroelectric energy |
Powys's Lakes
Powys is the largest county in Wales and has many reservoirs, especially in the Elan Valley.
| Lake name | Main River | Location | Size (acres) | What it's used for |
|---|---|---|---|---|
| Beacons Reservoir | River Taff | SN987182 | 52 | Supplies water |
| Caban-coch Reservoir | River Severn | SN924645 | 500See note | Supplies water |
| Claerwen Reservoir | River Severn | SN854651 | 664 | Supplies water |
| Llyn Clywedog | River Severn | SN911870 | Helps control river flow | |
| Llangorse Lake | River Usk | SO132266 | 327 | A natural lake, the largest in South Wales |
| Lake Vyrnwy | River Vyrnwy | SH989213 | Supplies water |
Note: Caban Coch and Garreg-ddu reservoirs are named separately but usually form one large area of water. The size given is for both combined.
Lakes in National Parks
Wales has three beautiful national parks, and many lakes are found within their borders.
Brecon Beacons National Park
This park is known for its mountains and reservoirs.
| Lake name | Main River | Location | Size (acres) | What it's used for | Area(s) |
|---|---|---|---|---|---|
| Beacons Reservoir | River Taff | SN987182 | 52 | Supplies water | Powys |
| Llangorse Lake | River Wye | SO132266 | 327 | A natural lake | Powys |
| Llwyn-on Reservoir * | River Taff | SO012113 | 150 | Supplies water | Merthyr Tydfil, Rhondda Cynon Taf |
| Usk Reservoir | River Usk | SN832288 | Supplies water | Carmarthenshire, Powys |
Pembrokeshire Coast National Park
This park is famous for its stunning coastline, but it also has some lakes.
| Lake name | Main River | Location | Size (acres) | What it's used for | Area(s) |
|---|---|---|---|---|---|
| Bosherston Lakes | Coastal stream | SR974946 | Man-made lakes | Pembrokeshire | |
| Rosebush Reservoir, Rosebush | Western Cleddau | SN061291 | 30 | Supplies water | Pembrokeshire |
Snowdonia National Park
Snowdonia is a mountainous region with many beautiful, often natural, lakes.
| Lake name | Main River | Location | Size (acres) | What it's used for | Area(s) |
|---|---|---|---|---|---|
| Llyn Arenig Fawr | River Dee | SH846380 | 84 | A natural lake, supplies water | Gwynedd |
| Llyn Celyn | River Dee | SH858405 | 815 | Helps control river flow | Gwynedd |
| Llyn Conwy | River Conwy | SH780462 | 101.3 | Supplies water for Llanrwst | Conwy |
| Llyn Cowlyd | River Conwy | SH727624 | 269 | Supplies water for Conwy | Conwy |
| Llyn Idwal | River Ogwen | SH645596 | 28 | Gwynedd | |
| Llyn Llydaw | River Glaslyn | SH629543 | 110 | Gwynedd | |
| Llyn Padarn | River Seiont | SH572613 | 280 | A natural lake used for fun activities | Gwynedd |
| Bala Lake – (Llyn Tegid) | River Dee | SH911338 | 1,196 | Gwynedd | |
| Llyn Trawsfynydd | River Dwyryd | SH674377 | 1,180 | Used for nuclear power (in the past) & hydroelectric energy | Gwynedd |
Welsh Lakes Supplying Water to England
While many Welsh lakes provide water for Wales itself, some important reservoirs were built to supply water to towns and cities in England.
Here are some of the main reservoirs that do this:
| Reservoir name | Location | Built by | Supplies water to |
|---|---|---|---|
| Lake Vyrnwy | Powys | Liverpool Corporation | Liverpool, Cheshire and Manchester |
| Claerwen | Elan Valley reservoirs | Birmingham Corporation Water Department | Birmingham |
| Craig-goch | Elan Valley reservoirs | Birmingham Corporation Water Department | Birmingham |
| Pen-y-garreg | Elan Valley reservoirs | Birmingham Corporation Water Department | Birmingham |
| Garreg-ddu | Elan Valley reservoirs | Birmingham Corporation Water Department | Birmingham |
| Caban-coch | Elan Valley reservoirs | Birmingham Corporation Water Department | Birmingham |
| Alwen Reservoir | Conwy | The Corporation of Birkenhead | Birkenhead |
| Llyn Celyn (via and Bala Lake) | Gwynedd | Liverpool Corporation Waterworks | Liverpool |
| Llyn Clywedog | Powys | Reed and Mallick of Salisbury | Shropshire, West Midlands to Bristol |
Former Lakes
Some lakes that once existed in Wales are no longer there, or their use has changed. These were often industrial ponds or reservoirs that are now gone or have been changed.
| Lake name | Main River | Location | Size (acres) | What happened to it | Area |
|---|---|---|---|---|---|
| Bryn-bach Pond | Sirhowy River | SO122100 | Used for industry in the past | Blaenau Gwent | |
| Lower Neuadd Reservoir | River Taff | SO030180 | Former reservoir (dam broke) | Merthyr Tydfil | |
| Llyn Nantlle-isaf | Afon Llyfni | SH506528 | A natural lake that is no longer there | Gwynedd |
See also
- List of standardised Welsh lake names in Snowdonia
