What is the River Severn?

The River Severn is the longest river in Britain, measuring about 180 miles (290 km) from its source to tidal waters, with its estuary adding approximately 40 miles (64 km). Rising near the River Wye on the northeastern slopes of Plynlimon in Wales, it flows in a semicircular direction southwards towards the Bristol Channel and the Atlantic Ocean. The river drains an area of 4,350 square miles (11,266 square km). The Severn's course initially descends southeasterly from 2,000 feet (600 meters) at its source to 500 feet (150 meters) at Llanidloes, Wales, before turning sharply northeastward through the Vale of Powys. It then flows eastward, looping around Shrewsbury. Its original eastward path to the River Dee was blocked by ice during the Pleistocene Epoch, redirecting its flow southeastward at Ironbridge.

Where does the River Severn start and end?

The River Severn, Britain's longest river, stretches approximately 180 miles (290 km) from its source to its tidal waters; the Severn Estuary adds about 40 miles (64 km) to its total length. The river starts near the River Wye on the northeastern slopes of Plynlimon (Welsh: Pumlumon) in Wales. From there, it follows a semicircular course, heading basically southward to the Bristol Channel and the Atlantic Ocean. The Severn Estuary eventually widens between South Wales and Somerset before becoming the Bristol Channel.

Why is the River Severn important in the United Kingdom?

The River Severn is the longest river in Britain, stretching about 180 miles from its source to its tidal waters, with an additional 40 miles in its estuary. Rising on the northeastern slopes of Plynlimon in Wales, it follows a semicircular path to the Bristol Channel and the Atlantic Ocean, draining an area of 4,350 square miles. The Severn has been historically important for industry, such as the early iron industry of Coalbrookdale, and for transportation and linking various regions via canals. Today, the Severn Bridge and the Second Severn Crossing (now the Prince of Wales Bridge) are vital motorway links between London and South Wales. Additionally, the river's water is used for cooling at the Berkeley atomic power station.

Which towns and cities does the River Severn flow through?

The River Severn, Britain’s longest river, flows through several towns and cities in Wales and England. Rising on the northeastern slopes of Plynlimon in Wales, the river's course runs southeasterly before turning northeastward through the Vale of Powys, passing Newtown and Welshpool. After its confluence with the River Vyrnwy at Llanymynech, the Severn flows eastward, looping around Shrewsbury . It then continues southward, passing through Stourport and Worcester , where the cathedral overlooks the river. Further downstream, the Severn receives the River Teme and then the River Avon at Tewkesbury , before reaching Gloucester , where it becomes tidal. The town of Bridgnorth lies along the River Severn. Finally, the river widens into an estuary between South Wales and Somerset, becoming the Bristol Channel.

What natural features or wildlife can be found along the River Severn?

The River Severn is Britain’s longest river, at approximately 180 miles (290 km) long, excluding the Severn estuary, which adds about 40 miles (64 km). The Severn has a notable tidal bore , a wave caused by the incoming tide. The river also supports a variety of coarse fish.

What is the Severn Bore, and why is it special?

The Severn Bore is a tidal bore that occurs on the River Severn in England. A tidal bore is a body of water that rushes up a river or estuary during exceptionally high sea tides, occurring where there is a large tidal range and the incoming tide is confined to a narrow channel. The Severn Bore is notable because the Severn Estuary has a high tidal range, and the river's channel narrows, creating the right conditions for a substantial bore to form.

River Severn

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Welsh:: Hafren

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River Severn

river, Wales and England, United Kingdom

Also known as: Hafren

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What is the River Severn?
The River Severn is the longest river in Britain, measuring about 180 miles (290 km) from its source to tidal waters, with its estuary adding approximately 40 miles (64 km). Rising near the River Wye on the northeastern slopes of Plynlimon in Wales, it flows in a semicircular direction southwards towards the Bristol Channel and the Atlantic Ocean. The river drains an area of 4,350 square miles (11,266 square km).

The Severn's course initially descends southeasterly from 2,000 feet (600 meters) at its source to 500 feet (150 meters) at Llanidloes, Wales, before turning sharply northeastward through the Vale of Powys. It then flows eastward, looping around Shrewsbury. Its original eastward path to the River Dee was blocked by ice during the Pleistocene Epoch, redirecting its flow southeastward at Ironbridge.
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Where does the River Severn start and end?
The River Severn, Britain's longest river, stretches approximately 180 miles (290 km) from its source to its tidal waters; the Severn Estuary adds about 40 miles (64 km) to its total length.

The river starts near the River Wye on the northeastern slopes of Plynlimon (Welsh: Pumlumon) in Wales. From there, it follows a semicircular course, heading basically southward to the Bristol Channel and the Atlantic Ocean. The Severn Estuary eventually widens between South Wales and Somerset before becoming the Bristol Channel.
4 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
Why is the River Severn important in the United Kingdom?
The River Severn is the longest river in Britain, stretching about 180 miles from its source to its tidal waters, with an additional 40 miles in its estuary. Rising on the northeastern slopes of Plynlimon in Wales, it follows a semicircular path to the Bristol Channel and the Atlantic Ocean, draining an area of 4,350 square miles.

The Severn has been historically important for industry, such as the early iron industry of Coalbrookdale, and for transportation and linking various regions via canals. Today, the Severn Bridge and the Second Severn Crossing (now the Prince of Wales Bridge) are vital motorway links between London and South Wales. Additionally, the river's water is used for cooling at the Berkeley atomic power station.
2 Britannica Sources
1. River Severn
2. River Avon
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Which towns and cities does the River Severn flow through?
The River Severn, Britain’s longest river, flows through several towns and cities in Wales and England. Rising on the northeastern slopes of Plynlimon in Wales, the river's course runs southeasterly before turning northeastward through the Vale of Powys, passing Newtown and Welshpool.

After its confluence with the River Vyrnwy at Llanymynech, the Severn flows eastward, looping around Shrewsbury. It then continues southward, passing through Stourport and Worcester, where the cathedral overlooks the river. Further downstream, the Severn receives the River Teme and then the River Avon at Tewkesbury, before reaching Gloucester, where it becomes tidal. The town of Bridgnorth lies along the River Severn. Finally, the river widens into an estuary between South Wales and Somerset, becoming the Bristol Channel.
3 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
What natural features or wildlife can be found along the River Severn?
The River Severn is Britain’s longest river, at approximately 180 miles (290 km) long, excluding the Severn estuary, which adds about 40 miles (64 km). The Severn has a notable tidal bore, a wave caused by the incoming tide. The river also supports a variety of coarse fish.
3 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
What is the Severn Bore, and why is it special?
The Severn Bore is a tidal bore that occurs on the River Severn in England. A tidal bore is a body of water that rushes up a river or estuary during exceptionally high sea tides, occurring where there is a large tidal range and the incoming tide is confined to a narrow channel.

The Severn Bore is notable because the Severn Estuary has a high tidal range, and the river's channel narrows, creating the right conditions for a substantial bore to form.
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1. tidal bore
2. River Severn
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River Severn, Britain’s longest river from source to tidal waters—about 180 miles (290 km) long, with the Severn estuary adding some 40 miles (64 km) to its total length. The Severn rises near the River Wye on the northeastern slopes of Plynlimon (Welsh: Pumlumon), Wales, and follows a semicircular course basically southward to the Bristol Channel and the Atlantic Ocean. It drains an area of 4,350 square miles (11,266 square km) with an average discharge at Bewdley of 2,170 cubic feet (61.5 cubic metres) per second.

BridgnorthThe town of Bridgnorth, with the River Severn in the foreground, Shropshire, England.

The river’s course is at first southeasterly, descending from an elevation of 2,000 feet (600 metres) at its source to 500 feet (150 metres) at the Welsh town of Llanidloes. There it turns sharply northeastward, following the Vale of Powys past Newtown and Welshpool. At Llanymynech the River Vyrnwy joins the Severn: the tributary headwaters are dammed to form the reservoir of Lake Vyrnwy, supplying Liverpool with drinking water. The enlarged Severn turns eastward over a plain on which it loops around the old town of Shrewsbury. Originally the river continued eastward to join the River Dee (which originates in North Wales and drains northward to the Irish Sea), but its course was blocked by ice during the Pleistocene Epoch, and its waters escaped to the southeast at Ironbridge. This course was maintained after deglaciation. The swiftly flowing current through the gorge at Ironbridge was important to the early iron industry of Coalbrookdale. Continuing southward, the Severn receives the River Stour at Stourport and passes through Worcester, where the cathedral stands on a cliff rising from the river’s steep left bank. The River Teme enters from the west below Worcester and the Avon from the northeast at Tewkesbury, a yachting and motorboat centre. At Gloucester the Severn becomes tidal and meanders to the sea. Navigation is difficult on this section and is bypassed by a ship canal (opened 1827), which leaves the estuary at Sharpness. Other canals that join the river, linking it with the Midlands region of England and with the River Thames, are virtually disused.

The estuary widens gradually between South Wales and Somerset and eventually becomes the Bristol Channel. Since the destruction of the railway bridge between Sharpness and Lydney in the late 1960s, rail traffic has been serviced by the Severn Tunnel, 15 miles (24 km) farther downstream. The Severn Bridge, an impressive suspension bridge with a 3,240-foot (990-metre) main span, was built in the 1960s and forms part of a motorway link (M48) from London to South Wales. An increase in automobile traffic led to construction of the 1,500-foot (456-metre) Second Severn Crossing (renamed the Prince of Wales Bridge in 2018), which opened in 1996 and carries the M4 motorway. The atomic power station (opened 1962) on the flats at Berkeley uses Severn water for cooling purposes. The Severn’s estuary has a notable tidal bore—i.e., a wave caused by the incoming tide.