Severn (Italian Wikipedia)

(EN) NRFA Station Mean Flow Data - Bewdley, su National River Flow Archive. URL consultato il 28 luglio 2015.
(EN) NRFA Station Mean Flow Data - Haw Bridge, su National River Flow Archive. URL consultato il 28 luglio 2015.

go4awalk.com

(EN) Water for life and livelihoods - River Basin Management Plan Severn River Basin District (PDF). URL consultato il 28 luglio 2015.
(EN, CY) River Severn Drought Order - Environmental Report (working draft) (PDF), Bristol, Environment Agency, Dicembre 2013, p. 15. URL consultato il 29 luglio 2015.
«The River Severn is the longest river in Great Britain, travelling approximately 354 km (220 miles) from its source in Plynlimon down to the Severn Estuary. [...] the catchment covers approximately 11,420 km² with an estuary over five miles wide. The Severn has twenty one
tributaries and flows through [...] Powys, Shropshire, Worcestershire and
Gloucestershire.»
(EN) Severn Tidal Power Feasibility Study: Conclusions a nd Summary Report (PDF), Ottobre 2010. URL consultato il 29 luglio 2015.

(EN) The Severn Railway Tunnel of the Great Western Railway, su greatwestern.org.uk. URL consultato il 29 luglio 2015.

(EN) 1015873 - The National Heritage List for England | Historic England, su historicengland.org.uk. URL consultato il 28 luglio 2015.
(EN) 1015325 - The National Heritage List for England | Historic England, su historicengland.org.uk. URL consultato il 28 luglio 2015.

(EN) Rhiannon Batten, The complete guide: The River Severn, su independent.co.uk, 10 agosto 2002. URL consultato il 29 luglio 2015.
«Britain's longest river begins its journey at a boggy spot just over 1,968ft above sea level on Plynlimon in the Cambrian mountains. The source is marked by two huge wooden posts, one inscribed in Welsh and one in English. [...] The Severn's tributaries include the Teme, Stour, Wye, Vyrnwy, Tern and Avon. [...] There are 100 bridges across the Severn, including the eponymous Severn Bridge. There are other road bridges, railway bridges, footbridges, farm bridges, toll bridges [...] One of the world's biggest bores [...] There are about 260 bores on the Severn each year, usually two a day on about 130 days a year, around the vernal and autumnal equinoxes (February to April and August to October). There are especially large bores on about 25 days a year [...] the Severn Bore is one of the highest in the world. [...] The bore travels 21 miles [...]»

(EN) FAQ - Tide Predictions and Data - NOAA Tides & Currents, su tidesandcurrents.noaa.gov. URL consultato il 29 luglio 2015.
«Q: Where are the highest tides? Below is a listing of 50 locations from around the world where the largest range of tides that have been observed.»

(EN) The 10 Longest Underwater Tunnels in the World, su therichest.com. URL consultato il 29 luglio 2015.

(EN) Noel J. Riggs,Steve B. Scott, The Top 5 Highest Tides on Earth, su top5ofanything.com. URL consultato il 29 luglio 2015.

(EN) Ironbridge Gorge - UNESCO World Heritage Centre, su unesco.org. URL consultato il 29 luglio 2015.
«[...] the Iron Bridge[...] is the first known metal bridge. It was built in 1779 by Abraham Darby III from the drawings of the architect Thomas Farnolls Pritchard.»

(EN) Lou Johnson, Plynlimon and Nant-y-Moch Reservoir - Cambrian Mountains Ceredigion - Walk 1102 - a walk description from Walking Britain, su walkingbritain.co.uk. URL consultato il 29 luglio 2015.
«Plynlimon is the highest point in mid-Wales and also the high plateau watershed from which two major rivers: the Severn and the Wye derive their source.»

Severn Estuary Partnership - Working in partnership for the future of the Severn Estuary, su severnestuary.net. URL consultato il 29 luglio 2015 (archiviato dall'url originale il 23 luglio 2011).
SEVERN BORE TIMETABLE 2015 | 2015 Tide Times | 2016 Timetable | Tidal info, su thesevernbore.co.uk. URL consultato il 29 luglio 2015 (archiviato dall'url originale il 22 agosto 2015).
(EN) 1004780 - The National Heritage List for England | Historic England, su historicengland.org.uk. URL consultato il 28 luglio 2015 (archiviato dall'url originale il 26 settembre 2015).
(EN) Severn River Crossing - History, su severnbridge.co.uk. URL consultato il 29 luglio 2015 (archiviato dall'url originale il 2 agosto 2015).
«The Severn Bridge was opened in 1966 to replace the ferry service crossing from Aust to Beachley. The new bridge provided a direct link for the M4 motorway into Wales. [...] Between 1980 and 1990 traffic flows increased by 63% and there were severe congestion problems in the summer and at peak times each day. Further increases in traffic flows were expected in the years ahead. [...]to build a second Crossing at English Stones, some 5km downstream of the existing Bridge. [...] The new Crossing was opened on 5 June 1996 by His Royal Highness, The Prince of Wales.»