Second Severn Crossing

The Severn Tunnel (Welsh: Twnnel Hafren) is a railway tunnel in the United Kingdom, linking South Gloucestershire in the west of England to Monmouthshire in south Wales under the estuary of the River Severn. It was constructed by the Great Western Railway (GWR) between 1873 and 1886 for the purpose of dramatically shortening the journey times of their trains, passenger and goods alike, between South Wales and Western England. It has often been regarded as the crowning achievement of GWR's chief engineer Sir John Hawkshaw.Prior to the tunnel's construction, lengthy detours were necessary for all traffic between South Wales and Western England, which either used ship or a lengthy diversion upriver via Gloucester. Recognising the value of such a tunnel, the GWR sought its development, tasking Hawkshaw with its design and later contracting the civil engineer Thomas A. Walker to undertake its construction, which commenced in March 1873. Work proceeded smoothly until October 1879, at which point significant flooding of the tunnel occurred from what is now known as “The Great Spring”. Through strenuous and innovative efforts, the flooding was contained and work was able to continue, albeit with a great emphasis on drainage. Structurally completed during 1885, the first passenger train was run through the tunnel on 1 December 1886, nearly 14 years after the commencement of work. Following its opening, the tunnel quickly formed a key element of the main trunk railway line between southern England and South Wales. Amongst other services, the GWR operated a car shuttle train service through the tunnel for many decades. However, the tunnel has also presented especially difficult conditions, both operationally and in terms of infrastructure and structural maintenance. On average, around 50 million litres of water per day infiltrates the tunnel, necessitating the permanent operation of several large pumping engines. Originally, during much of the steam era, a large number of pilot and banking locomotives were required to assist heavy trains traverse the challenging gradients of the tunnel, which were deployed from nearby marshalling yards. The tunnel is 7,008 m (4.355 mi) long, although only 3,621 m (2.250 mi) of its length are under the river. It was the longest underwater tunnel in the world until 1987 and, for more than 100 years, it was the longest mainline railway tunnel within the UK. It was finally exceeded in this capacity during 2007 with the opening of the two major tunnels of High Speed 1, forming a part of the Channel Tunnel Rail Link. In 2016, overhead line equipment (OHLE) was installed in the tunnel to allow the passage of electric traction; this work was undertaken as one element of the wider 21st-century modernisation of the Great Western main line.

Portskewett Pier was a station on the Bristol & South Wales Union Railway. The pier at Black Rock, near Portskewett, was the Welsh side of the New Passage Ferry across the River Severn. The ferry linked rail services between Bristol and South Wales, avoiding the previous long detour through Gloucester. The ferry service lasted for nearly twenty five years, from 1863 to 1886, until the opening of the railway tunnel beneath the river.

Sudbrook is a village in Monmouthshire, south east Wales. It is located 4 miles south west of Chepstow and 1 mile east of Caldicot. It lies close to the Second Severn Crossing on the Severn Estuary, and adjoins the village of Portskewett. It was largely built in the late 19th century for workers on the Severn railway tunnel. At that time it was also known as Southbrook.

The English Stones are a rocky outcrop in the Severn Estuary between Caldicot, Monmouthshire, and Severn Beach, South Gloucestershire. Because the area is exposed at low tide, and is a rare spot of solid land in the highly tidal estuary, it has long been considered a good location to build barrages, dams or bridges. In the 1990s the construction of the Second Severn Crossing made use of the English Stones as a foundation for significant sections of the bridge.

Portskewett railway station is a former station serving Portskewett, Wales, four miles south west of Chepstow and one mile east of Caldicot. It was opened as a broad gauge line with the South Wales Railway in 1850 and closed to passengers in 1964. Between 8 September 1863 and 1886 the station was known as Portskewett Junction, where the Bristol and South Wales Union Railway diverged for the New Passage Ferry crossing to Bristol. This new station was at a location 800 yards east of the original location. The opening of the Severn Tunnel in 1886 made the ferry at Black Rock redundant. The station was twin platform with a footbridge. The footbridge and the twin track line remain in use today. Portskewett Pier railway station was opened on 1 January 1864 and closed 1 December 1886.

On 7 December 1991, two trains collided inside the Severn Tunnel, between England and Wales. There were no fatalities but 185 passengers were injured.

St Mary's is located in the centre of the village of Portskewett, Monmouthshire. It is a Grade I listed building as of 19 August 1955.

Portskewett (Welsh: Porthsgiwed or Porthysgewin) is a village and community (parish) in Monmouthshire, south east Wales. It is located four miles south west of Chepstow and one mile east of Caldicot, in an archaeologically sensitive part of the Caldicot Levels on the Welsh shore of the Severn Estuary. The Second Severn Crossing passes overhead carrying the M4 motorway. The community includes Sudbrook, Crick and Leechpool.

Manor Farmhouse and Manor Cottage, Portskewett, Monmouthshire is a country house dating from early 17th century. The house is a Grade II* listed building.

St Pierre is a former parish and hamlet in Monmouthshire, south east Wales, 3 miles (4.8 km) south west of Chepstow and adjacent to the Severn Estuary. It is now the site of a large golf and country club, the Marriott St Pierre Hotel & Country Club, which was previously a large manor house and deer park belonging to the Lewis family.

The Gatehouse and attached range, at the St Pierre Hotel, St Pierre, Mathern, Monmouthshire are the most significant remains of the mansion built by the Lewis family in the late 15th century and owned by them until 1924. The original house was built by William Lewis, and extended by his son George, between 1475 and 1508. After the Lewises sold up, the house had a variety of owners and was converted to the clubhouse of a golf club in 1962. It has since been massively extended as a hotel and country club. The gatehouse and range have Grade II* listed building status. The surrounding gardens are included on the Cadw/ICOMOS Register of Parks and Gardens of Special Historic Interest in Wales.

Severn Beach railway station serves the village of Severn Beach, England. The station is the terminus of the Severn Beach Line. This station is 13.5 miles (21.7 km) north west from Bristol Temple Meads on the Severn Beach Line. The station is managed by Great Western Railway, who are also the sole provider of trains serving the station.