Sea of Marmara
A small inland sea linking the Black Sea and Aegean, rich in history and mythology.
Last updated
The Sea of Marmara is a small inland sea entirely within Turkey's borders, connecting the Black Sea and Aegean Sea via the Bosporus and Dardanelles straits.[1]
Key facts and history
The sea is named after Marmara Island, which is rich in marble, from the Greek word for marble.[2] The August 1999 earthquake is called the Marmara Earthquake because its epicentre lay under the sea.[3] The basin is home to about one-third of Turkey's population, with Istanbul being the largest city on its shores.[4] During classical times, the sea was referred to as the Propontis, a Greek term meaning "in front of the sea," which described its position relative to the Black Sea.[5]
According to Greek mythology, the Argonauts were driven by a storm back to an island in the Propontis, where they mistakenly fought and killed King Cyzicus; the killing is attributed to either Jason or Heracles.[6] Beneath this sea lies the North Anatolian Fault, which caused significant earthquakes in August 1999 (the Izmit event) and November 1999 (the Düzce event).[3] A Russian oil tanker split apart on 29 December 1999 during a storm, releasing more than 1,500 tonnes of oil into the water.[7] The sea faces severe strain from fast-growing populations and unchecked building development in the surrounding region.[4]
What the cited sources add
The Guinness World Records entry confirms the Sea of Marmara is the smallest true sea, with dimensions of 280 km long and 80 km wide.[8] That source gives an average depth of 494 m and a maximum depth of 1,355 m in the centre.[8] Official boundaries for the sea are established by the International Hydrographic Organization.[9] Untreated or minimally treated waste was discharged into the Marmara Sea for many years, exceeding its natural capacity to absorb pollutants.[4]
Consequently, numerous marine species have vanished, and fishing in the East Bay was prohibited for an extended period because of extreme contamination.[4] From January to June 2021, a mucilage event occurred, resulting in damage to habitats and economic difficulties.[4]
References
- Wikipedia, "Sea of Marmara" (CC BY-SA 4.0), which cites: "Marmara, Sea of - Dictionary definition of Marmara, Sea of - Encyclopedia.com: FREE online dictionary", www.encyclopedia.com; "Smallest sea", Guinness World Records, 20 March 2026 (we also read that source) en.wikipedia.org
- Wikipedia, "Sea of Marmara" (CC BY-SA 4.0), which cites: Liddell, "A Greek-English Lexicon", Perseus (original not read by us) en.wikipedia.org
- Wikipedia, "Sea of Marmara" (CC BY-SA 4.0), which cites: "Marmara earthquake: 20 years on", IFRC, 16 August 2019 (original not read by us) en.wikipedia.org
- Wikipedia, "Sea of Marmara" (CC BY-SA 4.0), which cites: Albay, "Mucilage Problem in the Sea of Marmara", Istanbul University Press, 2023 (original not read by us) en.wikipedia.org
- Wikipedia, "Sea of Marmara" (CC BY-SA 4.0) en.wikipedia.org
- Wikipedia, "Sea of Marmara" (CC BY-SA 4.0), which cites: Parada, "Greek Mythology Link" (original not read by us) en.wikipedia.org
- Wikipedia, "Sea of Marmara" (CC BY-SA 4.0), which cites: Otay, "The Volgoneft-248 Oil Spill in the Marmara Sea", ResearchGate, January 2001 (original not read by us) en.wikipedia.org
- "Smallest sea", Guinness World Records, 20 March 2026. facts only, no text reused. guinnessworldrecords.com
- Wikipedia, "Sea of Marmara" (CC BY-SA 4.0), which cites: "Limits of Oceans and Seas", International Hydrographic Organization, 1953 (original not read by us) en.wikipedia.org
Each numbered sentence above was checked against the source it cites before publication. Sentences citing Wikipedia adapt text from the English Wikipedia article Sea of Marmara (contributors), used under CC BY-SA 4.0; this entry is available under the same licence. Other sources were used for facts only; no text or images are copied from them.
More in Seas And Oceans
Sources
Compiled from Wikipedia and the sources listed below. Text from Wikipedia is available under CC BY-SA 4.0; this entry is adapted from it.
- Wikipedia: Sea of Marmara (CC BY-SA 4.0).
Spotted an error? Know more?
Reader corrections go straight into our review queue. Suggest an edit · How this site is sourced