Garth Hill

Garth Hill

Garth Hill rises above Pentyrch and Gwaelod-y-Garth, northwest of Cardiff. The recorded height is 306.9 m. At ST103835, the trig point stands on an ancient burial mound; DoBIH records ground 510 m east-northeast as 6.4 m lower. The mound and eastern shoulder are distinct summit features.

Returning walking routes

The BBC’s Pentyrch circuit starts and finishes outside the Lewis Arms. It links Coed y Bedw, Georgetown and Gwaelod-y-Garth with the summit, returning south over the Ridgeway Walk and Mountain Road. Its approximately 4.5 miles converts to about 7.2 km. It has steep sections, steps and stiles; no duration or ascent figure is published.

Cardiff Ramblers’ longer circuit starts and finishes at Radyr station car park. It visits Forest Farm, Morganstown, the Garth summit, Taffs Well and Castell Coch before returning along the Taff. The source gives 16.5 km, 400 m of climbing and a strenuous description, without a duration. These figures belong to this full circuit and must not be transferred to the shorter walk.

The planning notes summarise the complete returns. Carry detailed mapping and the original source directions, and check current access notices rather than relying on older descriptions alone.

Access and facilities

The summit grid reference is not a parking location. Arrange lawful parking for the chosen start and check restrictions. Do not assume that pub car parks are available for a walk. Taffs Well and Radyr provide railway approaches, and Cardiff Bus 136 serves Pentyrch; check travel times for your date and the last return. The Gwaelod y Garth Inn offers refreshments below the hill, subject to opening times. Bring supplies for the ridge and do not rely on toilets at Taffs Well station.

Terrain, safety and views

Grassy slopes and woodland paths can be steep, muddy and slippery. The longer circuit includes a rocky descent, roads and a railway crossing. Coed y Bedw has steps and stiles, requires dogs on leads and manages ash dieback: follow all closure signs. Keep clear of steep drops, give livestock space and protect the burial mounds. The ridge is exposed to wind and poor visibility. On clear days the outlook includes Cardiff, the Taff Valley and the Bristol Channel.

Heol Goch suffered flood-related disruption in 2026. Cardiff Bus reported its reopening and resumed routes from 6 August, with temporary lights. That dated notice does not guarantee all paths or future road access; check for current works and restrictions before travelling.

Geology, name and history

Garth Hill includes Pennant Sandstone, part of the Carboniferous succession of the South Wales Coalfield. These sandstone beds are interleaved with thinner mudstone and siltstone layers. The limestone of nearby Little Garth is a separate geological feature; the exact bed beneath the summit mound has not been established here.

The name uses Welsh garth, meaning a hill or ridge. Owen and Morgan’s place-name dictionary places Gwaelod-y-garth under this topographical sense, distinct from the separate sense meaning an enclosure.

Cadw records five Bronze Age round barrows on the ridge, scheduled as GM107. The trig-point mound is an ancient earthwork, not evidence that villagers recently raised the hill. Nearby separate hill destinations include Craig yr Allt (273 m) and Caerphilly Common (270.8 m).