Former island
island that once existed
A former island is a mass of land that was once an island, but has been joined to a mainland, another island, or engulfed by a body of water. The process of joining might be the result of volcanic activity, moving tidal sands, or through land reclamation. Islands engulfed by the sea may have submerged because of subsidence, tectonic activity, erosion, or rising sea levels. For example, the New Moor island in Bangladesh existed in the 1970s, but was engulfed by the Bay of Bengal in 2011.
Examples
Eldøyane, a partially artificial former island in Norway
Harriet Island, a former island in the Mississippi River in Saint Paul, Minnesota, now joined to the mainland of Saint Paul
Any of several former islands in the River Thames, England
Mount Muria, previously limited by the Muria Strait which has become shallow, now part of Java
Peñón de Vélez de la Gomera, a Spanish former island now joined to the Moroccan shore by a sandy isthmus
Sakurajima, a former island now joined to the mainland in Japan
Sevan Island, a former island in Armenia, now a peninsula
Urk and Schokland, two former islands now part of the reclaimed Noordoostpolder in the Netherlands, a polder reclaimed as part of the Zuiderzee Works designed by Cornelis Lely
Walcheren, a former island in the Netherlands now joined with Zuid-Beveland as part of the Delta Works to prevent flooding
See also
Ghost Island (disambiguation)
List of lost lands
Phantom island
Tied island
Further reading
Johnson, H & Kuwahara, S (2016), "Sakurajima: Maintaining an island essence", Shima: The International Journal of Research into Island Cultures, vol. 10, no.1, pp. 48–66.
Begin with the source’s own compact description: “Former island” is island that once existed. The dossier treats that line as a proposition to test through Former, island and once, not as a finished interpretation.
Why this record matters
The phrase “island that once existed” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.
Maps, plans, fabric surveys and administrative records can establish how the site’s name, extent and function changed over time. The source revision retrieved here is dated Jun 26, 2026. The linked authority identifier is Q52103661. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2011 and 2016.
Architectural summaries often privilege surviving fabric and can understate demolished phases, contested use or displaced communities. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Treat names, boundaries and functions as historically changeable. Maps, plans, inventories and administrative records can clarify what the place meant at different dates.
- Historic place names
- Jurisdictional context
- Routes into maps and plans
Contemporary maps, plans, listed-building records, estate papers and the responsible local or national archive.
Three-step research path
- Establish the record: confirm the title “Former island”, its source revision and the description used here.
- Expand the search: follow Former island primary sources, Former island archive and Former research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Former island”?
- Which earlier names or jurisdictions may reveal additional records?
- Which authority defined the place, boundary or structure at the relevant date?
Search terms from this dossier
This entry incorporates text from “Former island” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.