This walk was researched before the Covid-19 lockdown & is published in anticipation of freer movement in the months ahead.
This is a circular walk around the Portskewett area in South Wales which offers some glimpses into railway links between England and Wales over the last 150 years. The walk distance from Caldicot station is 10.5 km (6½ miles).
OS Map: Bristol West & Portishead Congresbury & Chew Magna
Sheet 154 – Explorer 1:25 000 scale
Journey time from Bristol Temple Meads: 35-65 mins – varies due to connection time at Severn Tunnel Junction
- Bristol Temple Meads to Severn Tunnel Junction – 25 minutes, hourly service
- Severn Tunnel Junction to Caldicot – 2 minutes, hourly service
The walk could be done from Severn Tunnel Junction, but this would add on another mile at start and end, so approximately 9 miles distance. Walkers will need an OS map as these directions are not detailed.
From Caldicot station walk east along the footpath south of Gloucester-Newport railway line. North of this line the South Wales Main Line dives underground. The footpath joins the Wales Coast Path underneath the M4 Second Severn Crossing, continue east towards Sudbrook.
The path passes the Iron Age Fort which has been eroded by the sea to form an arc to the shore. Beyond the fort are the ruins of the Trinity Chapel, the only building that remains of an abandoned medieval village.

Immediately after the chapel is modern Sudbrook village, built from 1873 to house those working on the excavation of the Severn Railway Tunnel. Increasing coal freight was being transported from South Wales and ferries across the Severn were unreliable due to tides and weather.
There were over 3000 workers on the Welsh side of the tunnel at any one time. The village consisted of villas for the managers, terraces for the workers, mission hall, school, hospital, coffee house and reading room. Many of the buildings were constructed from stone removed from the tunnel.
The large brick building is the pumping station. In October 1879 workmen hit an underground spring and it took 2 years and a courageous diver to drain the tunnel. In October 1883, a 6 foot tidal wave swept up the Severn flooding the village and inundating the workings. The pumping station is still in use today – up to twenty million gallons of water continue to flow into the tunnel daily. It is claimed that the tunnel would be full of water in 26 minutes if the pumps were switched off and back up measures failed.

Behind the fort, Bovis are building a large housing estate. Previously, this was a paper mill which used water pumped out of the tunnel in the manufacturing process. This water was also used by a brewery in Magor and in the Ordnance Factory at Caerwent. During construction of the Severn Tunnel, part of the paper mill site was a brickworks which supplied some of the 76,400,100 bricks used in the construction of the tunnel.
Follow the Wales Coast Path east through the village. Sudbrook Non-Political Club stands on the site of the former works pay office. The club holds the Sudbrook Historical Exhibition, which has a huge amount of information about the railway and local history. Check with the club for opening hours.
The (now disused) overground branch line brought construction materials to the site and coal to the pumping station and follows the line of the underground main line. You can feel the vibrations of trains 200 feet beneath your feet!
The Severn Tunnel opened for coal in September 1886, and then passengers from December 1886. The tunnel length is 4 miles 624 yards and it takes 3 minutes 40 seconds for a train to pass through. Many passengers will hardly notice – compare this to the experience of transiting from train to boat on a wooden pier where waves are crashing over the roof of the train!
From 2016 to 2019 Network Rail installed overhead line equipment to allow electric traction; this proved problematic due to salty, damp conditions in the roof of the tunnel. Nevertheless, electrification was completed and the first train ran from London Paddington to Cardiff under electric in January 2020.
Following the Wales Coast Path east, the route passes a large solar farm towards Black Rock, once a ferry crossing. In the era of tunnel construction this was a well-trodden route as Sudbrook was a teetotal village and the Black Rock Hotel served beer! The hotel served ferry passengers and was a popular destination in its own right with pleasure gardens, croquet, quoits and band concerts.
The hotel was demolished in the 1960s and the site is now the Black Rock picnic area where display boards illustrate the heritage lave net fishing techniques – fishermen stand in the shallows of the outgoing tide and catch the fish with hand held Y-shaped nets.
Roman coins have been found in the mud near the ferry slipway, showing that the crossing has been in use for centuries.
The Bristol & South Wales Union Railway arrived to the shore in 1863, and a wooden pier was built out into the estuary so that travelers could alight from their train directly beside the ferry. At low tide pier foundations are visible. On the English side of the crossing point, the line ran from New Passage/Redwick via Pilning (Low Level) to Bristol Temple Meads. The white buildings of Redwick can be seen across the water.

This service operated for 23 years, but stormy weather and the high Severn tidal range made the ferry unpredictable and dangerous. The 1886 Severn Tunnel opening rendered the ferry obsolete.
The walk follows the turnpike road inland towards Portskewett; the course of the BSWUR railway runs parallel to the road and dips under the road at the old bridge next to the railway cottages. Shortly thereafter the road crosses the Gloucester-Newport railway line.
Head west through Portskewett via Sunny Croft towards Station Road where you can cross the Gloucester-Newport railway line on the original Portskewett Junction station footbridge (station closed 1964). Here the BSWUR line diverged for Black Rock. South of the railway, the footpath follows fields west towards St Mary’s Church.
St Mary’s Church Portskewett dates from late 11th century and the churchyard contains graves of Cornish miners who worked in the Severn Tunnel construction. The park behind the church contains earthworks from a medieval manor.

At the opposite end of the park, a footpath follows the Gloucester-Newport railway to Caldicot Junction where the Sudbrook coal branch line forked south and the Caerwent branch forked north. The Caerwent line was built to serve a Ministry of Defence site in 1939 and remained in use for a munitions depot until 1993.
After the junction, either cross the Gloucester-Newport railway to the Wales Coast Path and retrace your steps west to Caldicot station, or stay north of the railway line and follow the roads back to Caldicot station.
Sudbrook History Society have contributed to an excellent leaflet about the area. This contains a useful walking map past similar points of interest, but with a detour to see the 4000-year old standing stones at Heston Brake Long Barrow.
Pilning and Severn Beach History Group have produced an interesting leaflet about the English side of the New Passage ferry crossing.
Severn Crossings – a timeline:
- To 1860s – “Old Passage” Aust-Beachley ferry crossing, likely to have operated since Roman times, closes when superceded by BSWUR crossing
- To 1863 – “New Passage” Redwick-Sudbrook ferry crossing, likely to have operated since Roman times
- 1852 – the Chepstow Railway Bridge across the Wye allows through trains from Cardiff to Gloucester (the “Great Way Round”)
- 1863–1886 – New Passage opens for Bristol and South Wales Union Railway rail/ferry interchange, closes when Severn Railway Tunnel opens
- 1879-1960 – Severn Railway Bridge Sharpness-Lydney, built for coal freight, also used for passengers, collapses after barge collision in 1960
- 1886 – Severn Railway Tunnel opens for South Wales Main Line railway
- 1924-1966 – GWR operates a car shuttle train between Pilning and Severn Tunnel Junction
- 1926-1966 – Old Passage re-opens for motor traffic, closes when Severn Bridge opens
- 1966 – Severn Bridge opens
- 1996 – Second Severn crossing opens