Zoe has given out a lot of the history of the dam. Let's just add a bit of local information to say that this is a hidden gem of a reservoir. Though well known by locals, it is still an under-visited location. There are lovely walks to be had either around it or through the adjacent forests, there is a cafe and a roadside service van with refreshments on the way around; and the trails are great. The forest views, quaint foot bridges, and views out over the water make it a very scenic area.

Zoe Evans

March 29, 2022

Hiking

Llwyn-on Reservoir (or Llwyn Onn Reservoir) is the largest and southernmost of the three reservoirs in the Taf Fawr valley in South Wales. Cardiff Corporation Waterworks obtained an Act of Parliament in 1884 to authorise construction of the reservoirs, to increase the water supply for Cardiff, but construction of Llwyn-on Reservoir did not start until 1911 and was completed in the 1920s.

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4.3

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269

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#1.

Llwyn-on Reservoir loop

5.50km

01:26

40m

Easy hike. Great for any fitness level. Easily-accessible paths. Suitable for all skill levels.

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Easy

4.3

(32)

265

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#2.

Llwyn-onn Reservoir loop

5.43km

01:26

50m

This easy 3.4-mile (5.4 km) Llwyn-onn Reservoir loop offers scenic views of deep blue waters, rolling hills, and tranquil woodlands.

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Easy

4.6

(12)

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#3.

Llwyn-on Reservoir – Llwyn-on Reservoir Dam loop from Llwyn-onn

9.55km

02:37

150m

Moderate hike. Good fitness required. Easily-accessible paths. Suitable for all skill levels.

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Moderate

Details

Informations

Elevation 270 m

Weather

Thursday 2 April

12°C

4°C

54 %

Additional weather tips

Max wind speed: 39.0 km/h

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Take Me There

Location: Merthyr Tydfil, South Wales, Wales, United Kingdom

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Llwyn-on Reservoir

#1.

Llwyn-on Reservoir loop

#2.

Llwyn-onn Reservoir loop

#3.

Llwyn-on Reservoir – Llwyn-on Reservoir Dam loop from Llwyn-onn

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