Islas Marías
archipelago
The Islas Marías ("Mary Islands") make up an archipelago in Mexico, consisting of four principal islands and five smaller islands/large offshore rocks. They are located in the Pacific Ocean, some 100 km (62 mi) off the coast of the state of Nayarit and about 370 km (230 mi) southeast of the tip of Baja California. They are part of the municipality (municipio) of San Blas, Nayarit. The islands were used as a penal colony until February 18, 2019, when President Andrés Manuel López Obrador ordered the closure of its operation as Islas Marías Federal Prison.
The first European to encounter the islands was Diego Hurtado de Mendoza, a cousin of Hernán Cortés in 1532, who gave them the name Islas Magdalenas. He found no evidence of prior habitation by the Native Americans. In 2010 the archipelago was designated the Islas Marías Biosphere Reserve by UNESCO.
Geography
The islands have an aggregate area of 244.97 km2 (94.58 sq mi) and a population of 1,116 on Isla María Madre as of the census of 2005 along with around 8,000 prisoners. The other islands are uninhabited. The main settlement is Puerto Balleto, with a population of 602.
Isla María Madre is the largest of the islands, with an area of 145.28 km2 (56.09 sq mi).
“Islas Marías” enters the record as archipelago. Crown Archives preserves that source wording while asking what Islas, Marías and archipelago can confirm, complicate or overturn.
Why this record matters
“Islas Marías” is worth following because a concise public description often conceals a longer documentary argument. Here, Islas, Marías and archipelago provides the most credible route into that argument.
The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Aug 28, 2026. The linked authority identifier is Q643715. Authority coordinates are 21.479, -106.456. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 2019, 1532, 2010 and 2005.
The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “Islas Marías”, its source revision and the description used here.
- Expand the search: follow Islas Marías primary sources, Islas Marías archive and Islas 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 “Islas Marías”?
- Which cited source is closest to the event, object or claim?
- Which institution is responsible for the underlying evidence?
Search terms from this dossier
This entry incorporates text from “Islas Marías” 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.