Lough Foyle , sometimes Loch Foyle  (from Irish: Loch Feabhail , which means “Feabhal’s loch”   ), is the mouth of the River Foyle. It lies between County Londonderry iNordirland and County Donegal in Ireland. Sovereignty over these waters has been disputed since the partition of Ireland.
Seen from space: Derry in the Ulster coast of Lough Swilly and Lough Foyle west to the east of the city ochInishowen.
Lough Foyle Ramsar site (wetland of international importance under the Ramsar Convention), is 2204.36 hectares in area, at latitude 55 05 N and longitude 24 07 01 37 W. It was designated a Ramsar on February 2, 1999. The site consists of a large shallow sea lough which includes the estuaries of the rivers Foyle, Faughan and Roe. It contains extensive areas of tidal mudflats and sand flats, salt marshes and associated brackish ditches. The site qualified under criterion 1 of the Ramsar Convention because it is a particularly good representative example of a wetland which plays a substantial hydrological, biological and ecological systems role in the natural functioning of a major river basin is located in a border location. The qualified even under the Ramsar criterion 2 because it supports a considerable number of rare, vulnerable or endangered species of plants and animals. A number of known species have been recorded for the Lough Foyle estuary and the lower parts of some of its tributary rivers. These include shad, shad, smelt and sea lamprey, which are all Irish Red List species.Important populations of Atlantic salmon migrate through the system to and from their spawning areas. 
The site is qualified even under the Ramsar criterion 3 as it supports a large number of wintering waterfowl including internationally important populations of whooper swans, light belliedPrutgås and bar-tailed godwit and wild bird species of national importance in an all-Ireland context, including the red-throated diver, great crested grebe, Mute Swan, Bewick’s swan, greylag , shelduck, teal, mallard, wigeon, eider ducks and red-breasted merganser. Nationally important wader species include Eurasian Oystercatcher, Eurasian golden plover, gray plover, lapwing, red knot, dunlin, curlew, redshank and greenshank. 
Flora and fauna
A survey of Lough Foyle was made between March 1937 and June 1939 by H. Blackler.  This map shows the distribution of some species of algae in the lough and a complete annotated list of algae recorded along with photographs of various locations. The list includes: cyanophyceae, Chlorophyceae, Phaeophyceae, Rhodophyceae, lichens and two species avZostera. The marine algae of Lough Foyle are also included in Morton (2003). 
The Royal Society for the Protection of Birds has a reserve on Lough. 
In 1792, the four mil Strabane Canal was constructed from the tidal waters of Lough Foyle at Leck, to Strabane. The canal fell into disuse in 1962. In June 2006 the Strabane Lifford Development Commission awarded a £ 1.3m cross-border waterways restoration contract. The project includes restoration of one and a half miles from the canal and two locks to working order. Work began on the Lough Foyle side of the canal in the summer of 2006, but in 2010 the partial restoration was considered unsatisfactory and the municipality refused to continue to maintain the channel. The Broharris canal was built in the 1820s, when an average, about two miles long on the south shore of Lough Foyle near Ballykelly was made towards Limavady. It served both as a drainage channel and a navigation with goods brought from Londonderry Port, seafood and kelp from the sand banks along the beach.
In the summer, operates a ferry service between Green and Magilligan of Lough Foyle.
Northern Ireland Railways runs from Londonderry train station along the scenic shores of Lough Foyle, with views of the Inishowen in County Donegal and the Atlantic Ocean via Coleraine to Belfast Central and Great Victoria Street .The strategic Belfast-Derry railway line is to be upgraded to facilitate more frequent trains and improvement of permanent way track and signaling to allow faster services.
From Londonderry railway station, the next stop is Bella Clean followed by Castle then Coleraine on his way to Belfast. Walkers access to the trains arrive at the Castle can go to Mussenden Temple is owned by the National Trust and can see the mouth of Lough Foyle and Green a bit away in County Donegal.
The main character of Alfred Bester’s famous science fiction novel, The Stars My Destination , named Gulliver Foyle. Bester took the names of their characters from different places in Ireland and the UK.
World War I
The United States Navy established a Naval Air Station, July 1, 1918 to operate seaplanes during the First World War. The base was closed shortly after the first armistice in Compiegne. 
At the end of World War II after the Allied victory, the rest of the Atlantic fleet of German U-boats used to attack supply lines from America to Britain during the Battle of the Atlantic gathered in Lough Foyle ochsank, as part of Operation Dead.
Lough Foyle is a disputed territory between Ireland and the United Kingdom after the Irish division in 1922 both sides claimed it was in its own territory.Although this dispute is still ongoing, there are currently no negotiations regarding its ownership. The State Department stressed its view June 2, 2009 that all the Lough Foyle is located in the UK, a spokesman states; “The British position is that the entire Lough Foyle is in the UK. We recognize that the Irish Government does not accept this position … There are no negotiations currently underway on this issue. The regulation of activities in the Lough is now responsible for the Loughs Agency, a cross-border bodies set up under the Belfast Agreement of 1998. ” 
- List of Loughs in Ireland
- List of Ramsar sites in Northern Ireland
- Wild Atlantic Way
- Ireland sharing
- Jump up ^ See Google Books, for example, published online.
- Jump up ^ Flanagan, Deirdre & Laurence, Irish place names , page 212. Gill & MacMillan, 2002. ISBN 0-7171-3396-6
- Jump up ^ placental NI Lough Foyle
- ^ Jump up to: ab “Especially and Proposed Ramsar sites in Northern Ireland” (PDF). Joint Nature Conservation Committee. Retrieved July 7, 2008.
- Jump up ^ Blackler, H. 1951st A study of algae Lough Foyle, Northern Ireland. Proc. R. Ir. . Acad 54B (6): 97-139
- Hoppa upp^Morton, O. 2003. Den marina makroalger i County Donegal, Irland .. Bull. Ir. biogeog. Soc. 27 : 3-164
- Jump up ^ Royal Society for the Protection of Birds
- Jump up ^ Van Wye, Adrian O. (1969). Naval Aviation in World War I, Washington, DC. Chief of Naval Operations. pp. 80th
- Hoppa upp^3 juni 14:08:52 BST 2009. “Londonderry Sentiniel, Foyle” loughed “i tvist – 3 juni 2009” . Londonderrysentinel.co.uk . Hämtad 4 april 2011 .