Islands in the River Thames

This article lists the islands in the River Thames, or at the mouth of a tributary (marked †), in England. It excludes human-made islands built as part of the building of forty-five two-gate locks which each accompany a weir, and islets subordinate to and forming part of the overall shape of another. The suffix -ey (pronounced today ) is common across England and Scotland and cognate with ait and meaning island, a term – as ait or eyot – unusually well-preserved on the Thames. A small minority of list entries are referred to as Island, Ait or Eyot and are vestiges, separated by a depression in the land or high-water-level gully.

Most are natural; others were created by excavation of an additional or replacement navigation channel, such as to provide a shorter route, a cut. Many result from accumulation of gravel, silt, wildfowl dung and plant decay and root strengthening, particularly from willows and other large trees. Unlike other large rivers, all today are considered fixed. All in the reaches below Lechlade have been protected against erosion by various combinations of canalisation of the river, building up with dredged material from the river bed, water reeds, concrete, cement, wood or sheet piling.

List of islands

The islands are listed in order upstream from the sea.

+ Islands from the sea to Thames Head and published size: Name Area(acre) Area(ha) ReferencesIsle of Sheppey†See article Isle of Sheppey for source. Its area is Two Tree Island† (also known as Leigh Marshes)Canvey Island†See article: Canvey Island for source. Its area is Its land forms the land part of a wider parish, which took in mud flats, saltings and eroded land to the south-east where the river is broad – its scope is stated to be 9055.442 acres per OS 25-inch map of 1898 Ordnance Survey Essex Sheet LXXVII SE revised 1895-1896, published 1898.http://www.visionofbritain.org.uk/unit/10244250/boundary boundary map of Canvey Island parish – Vision of Britain – The University of Portsmouth and othersLower Horse Island† on Holehaven† a sandbank of Holehaven Creek, CorringhamUpper Horse Island1.970.8Chiswick Eyot, ChiswickOS 25-inch map of 1910 Ordnance Survey Surrey II.10 revised 1910, published 1913.Oliver's Island, Strand-on-the-GreenOS 25-inch map of 1896 Ordnance Survey London LXXXIV published 1897.Brentford Ait, BrentfordOS 25-inch map of 1910 Ordnance Survey London sheet LXXXIV revised 1891-94, published 1897.Lot's Ait, BrentfordIsleworth Ait, IsleworthOS 25-inch map of 1910 Ordnance Survey London sheet XCVI revised 1891-94, published 1897.Corporation Island, Richmondapprox.Glover's Island, TwickenhamOS 25-inch map of 1894 Ordnance Survey London CXXII repeated on sheet CX published 1897.Eel Pie Island, TwickenhamOS 25-inch map of 1894, Surrey sheet VI.7 revised 1893-1894, published 1898.Swan Island, TwickenhamOS 25-inch map of 1894 Ordnance Survey London CXXII published 1897.Trowlock Island, TeddingtonSteven's Eyot, Kingston upon ThamesRaven's Ait, SurbitonOS 25-inch map of 1894, Middlesex sheet XXV.12 revised 1893-1894, published 1898.Boyle Farm Island, Thames DittonOS 25-inch map of 1895, Surrey sheet XII.7 revised 1895, published 1897.Thames Ditton Island, Thames DittonAsh Island, East MoleseyOS 25-inch map of 1894 Ordnance Survey London CXXXIX published 1897.Tagg's Island, HamptonGarrick's Ait, HamptonOS 25-inch map of 1894 Surrey sheet VI.14 published 1897. Ordnance SurveyBenn's Island, HamptonPlatts Eyot, HamptonOS 25-inch map of 1894-5 Middlesex sheets XXV.6 & 10 published 1896Grand Junction Isle, SunburySunbury Court Island, SunburyOS 25-inch map of 1893-4 Surrey sheet VI13 published 1896. Ordnance Survey. C. Measured as 2.464 by own research using online map tools; as east end sheared off rest slightly extendedRivermead Island, SunburyActual measurement. Compares to broader island OS 25-inch-to-mile map of Middlesex of 1912, sheet XXV.9 in four parcels, total . Published 1915.Sunbury Lock Ait, Walton on ThamesOS 25-inch-to-mile map of Middlesex of 1912, sheet XXV.9 in four parcels, total . Published 1915.Wheatley's Ait, Sunbury-on-Thames (also known as Wheatleys Eyot)OS 25-inch-to-mile map of Middlesex of 1912, sheet XXV.9, published 1915.Desborough Island, Walton-on-ThamesapproxD'Oyly Carte Island, WeybridgeOS 25-inch-to-mile map of Surrey of 1894, sheet XI.7 published 1896.Lock Island, SheppertonHamhaugh Island, SheppertonPharaoh's Island, SheppertonSince this source island has been made thinner to south-west to obstruct less of the main flow of the river, stated acreage reference number Shepperton: 226, measuring , named Dog AitLaleham Burway including Abbey Mead, ChertseyPenton Hook Island, LalehamOS 25-inch-to-mile map of Surrey of 1912, sheet V.14&15 published 1914Truss's Island, ThorpeChurch Island, Staines-upon-ThamesOS 25-inch-to-mile map of Buckinghamshire of 1899, sheet LVIII.8 published 1899Hollyhock Island with Holm Island, Staines-upon-ThamesThe Island (formerly marsh), Hythe EndMagna Carta Island, RunnymedePats Croft Eyot, RunnymedeAcreage number 198, WraysburyThe Island, WraysburyAcreage number 120, WraysburyFriary Island, WraysburyNo trench visible. No longer an islandOS 25-inch-to-mile map of Surrey of 1912, sheet IV.8 published 1914Friday Island, Old WindsorHam Island, Old Windsor Lion Island, Old WindsorSumptermead Ait, DatchetBlack Potts Ait, WindsorOS 25-inch-to-mile map of Buckinghamshire of 1897, sheet LVI.6 published 1899Romney Island, WindsorRomney Island is in three sections as broken by two short side weirs; it also has the long breakwater below Windsor Bridge called The CobblerCutlers Ait, WindsorFirework Ait, Windsor at most. This patch of less than six trees is too small to be shown on most maps of Windsor and EtonJacob's Island, WindsorNamed after Arthur Jacobs http://www.thamesweb.co.uk/windsorpeople/ArthurJacobs.htmlDeadwater Ait, WindsorBaths Island, Eton WickBush Ait, WindsorQueen's Eyot, DorneyMonkey Island, BrayOS 25-inch-to-mile map of Buckinghamshire of 1897, sheet LVII published 1899Pigeonhill Eyot, BrayHeadpile Eyot, BrayGuards Club Island, Maidenhead (also known as Bucks Ait)Bridge Eyot, MaidenheadGrass Eyot, MaidenheadRay Mill Island, MaidenheadNote: Ray Mill Island is fully attached to the bank on one sideBoulter's Island or Boulter's Lock Island, MaidenheadGlen Island, MaidenheadBavin's Gulls, Maidenhead (also known as Sloe Grove Islands)three main islands are marked from north to south.Formosa including manmade Mill and Sashes Islands, CookhamSheriff Island, MarlowGibraltar Islands, MarlowTemple Mill Island, HurleyFrog Mill Ait, HurleyOS Map sheet L1.11 of Bucks (county) revised 1897, published 1898.Black Boy Island, HurleyWith Frog Mill Ait, forms archipelago of three, these are the largest two, that to the north measured Magpie Island, MedmenhamFormerly two islands plus islet trees to south now all one. Pre-20th century maps show a narrow channel (between these); total published area then excluding filled in area: Hambleden Mill islandOS Map sheet L1.6 of Bucks (county) revised 1897, published 1898.Temple Island, RemenhamOS 25-inch-to-mile map of Oxfordshire of 1897, sheets LIV.5, LVI.13, LVI.14 and LVI1.16 published 1898Rod Eyot, Henley-on-ThamesFerry Eyot, HarpsdenPoplar Eyot, WargraveHandbuck Eyot, WargraveUnnamed Eyot, WargraveShiplake railway bridge islandShiplake weir islandPhillimore Island, CharvilThe Lynch, Lower ShiplakeHallsmead Ait, Lower ShiplakeMarginally washed away at upper end since last Ordnance Survey out-of-copyright published measurement givenBuck Ait, SonningGreatly washed away at upper end since last Ordnance Survey out-of-copyright published measurement givenLong Ait, SonningSonning Eye, Sonning including Aberlash House islandSonning Hill island, SonningSonning Marsh, Caversham Lakes IslandHeron Island, ReadingHeron Island was and island and downstream islet, marsh in 1898; one island below these former two islands was and has been given over to the riverView Island, ReadingWas in map cited however has been cut back to raise marshy eastern bulk and broaden main channel to southDe Bohun Island, ReadingFry's Island, Reading (also known as De Montfort Island)Pipers Island, ReadingSt Mary's Island and the Lower Large, Readingas to the Lower LargeAppletree Eyot, TilehurstPoplar Island, TilehurstMapledurham Mill IslandWhitchurch Mill Greater IslandLower Basildon marsh islandStreatley Mill Greater IslandCleeve Mill lower island, GoringCleeve Mill island, GoringCleeve Mill upper island, GoringCholsey Marsh islandFormer three separate aits merged by in-fill of channels per published mapsCrowmarsh Mill IslandLittle Wittenham Footbridge IslandClifton Cut IslandOS 25-inch-to-mile map of Oxfordshire of 1897, sheets XLV.16, XXXII.10 and XXXIX.2 published 1898Long Wittenham Backwater IslandCulham Cut IslandSutton Pools Island, Sutton CourtneyNag's Head Island, AbingdonAndersey Island, AbingdonTiger Island (opposite the Abbey Grounds), AbingdonLock Wood Island, Nuneham CourtenayFiddler's Elbow, Sandford-on-ThamesFiddler’s Elbow breaks into a 1.956 northern section (broken from the 8.631 remainder) by a minor, weired meandering creek in its northern part)Fidder's Elbow far northern sectionSwan Inn, Rose, Kennington or St Michael Isle, KenningtonFolly Island, Folly Bridge, OxfordA small island transected by Abingdon Road that lies between two spans of Folly Bridge.Osney Island, OxfordNote: Osney is given as its narrowest definition; its larger west parts of the city would more than treble this measurementFiddler's Island, OxfordGodstow Bridge IslandKing's Lock IslandPinkhill Lock IslandShifford Cut Island, Chimney Meadows, Chimney, OxfordshireRadcot Bridge Lower Island, RadcotOS 25-inch-to-mile map of Oxfordshire of 1898, sheets XXXVII.13 published 1899Radcot Bridge Upper Island, RadcotSwan Hotel Island, RadcotSt Mary's Mead, BuscotSt John's Bridge Island, Lechlade (borders Buscot)Northern meadow, Castle EatonCricklade north-east meadowIsland between High and Oaklake bridges†, Ashton KeynesManor stream island, Somerford Keynes and Kemble

List of former islands Frog Island†, Rainham Isle of Dogs, Poplar

Isle of Grain, Kent Thorney (or Thorney Island)† covered a broad area surrounding Westminster Abbey Bermondsey†, land and grounds of Bermondsey Abbey, formed by an anabranch (corollary channel) naturally dredged by the mouth of the Neckinger; a vestige of the channel is St Saviour's Dock. Battersea Formerly bounded by the Heath Brook, Falcon Brook and Thames. Beyond the alluvium/silts of the estuary, by the English Channel and North Sea Isle of Thanet†, Kent

Oxford floodplain In the Oxford area the river splits into several streams across the floodplain, which create numerous islands. On the right bank a large island is created by Seacourt Stream, Botley Stream and Bulstake Stream, and there are smaller islands, including the large mainly built-up island now known as Osney, created by streams between Bulstake Stream and the Thames, including Osney Ditch. The Oxford suburbs of Grandpont and New Hinksey are on an island created by Bulstake Stream, Hinksey Stream and Weirs Mill Stream. Iffley Meadows is an island west of Iffley Lock, between Weirs Mill Stream, Hinksey Stream and the Thames.

On the left bank Fiddler's Island followed downstream by the built-up island historically known as Osney lie between Castle Mill Stream and the Thames. Cripley Meadow is also on an island formed by Fiddler's Island Stream, Castle Mill Stream and Sheepwash Channel.

Eton and Dorney The status of Eton, Berkshire combined with Dorney is controversial. These are two mainly pre-1900-built small villages and their outlying localities: Eton Wick, Boveney and Dorney Reach. Much of these areas of land in the 19th century was marked by the Ordnance Survey "liable to floods" which led to pressure on authorities for flood protection, along with the more densely populated right bank.