# Minamidaitōjima (南大東島)
**Minamidaitōjima** (南大東島), also written Minami-Daito Island, is a raised coral atoll island in the Daito Islands of Okinawa Prefecture, [Japan](https://www.edgepedia.org/japan-epzdpsev89), lying about 360 to 400 km east of [Okinawa Island](https://www.edgepedia.org/okinawa-island) on the [Philippine Sea Plate](https://www.edgepedia.org/philippine-sea-plate).[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) • [2](https://www.env.go.jp/en/nature/biodic/kaiyo-hozen/kaiiki/engan/20901.html) It is the largest island of the Daito group, an oval of roughly 30.5 km² with a population of about 1,200 people, and it is administered as Minamidaito Village.[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) • [3](https://pmc.ncbi.nlm.nih.gov/articles/PMC8801181/)
| Key fact | Detail |
|---|---|
| Location | 25°50′N, 131°14′E, about 360 km east of Okinawa Island, on the Philippine Sea Plate[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) • [4](https://www.sciencedirect.com/science/article/pii/S2214581820301907) |
| Size | Area 30.52 km²; east-west 5.78 km, north-south about 6.54 km, coastline 20.8 km[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) |
| Population | 1,204 people in 695 households (May 31, 2024, resident registry)[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) |
| Geology | Uplifted atoll of dolomite and limestone; uplift rate about 0.05 m per thousand years[4](https://www.sciencedirect.com/science/article/pii/S2214581820301907) • [5](https://cir.nii.ac.jp/crid/1390001204229719168) |
| Discovery | First recorded by the Russian vessel Borodino in 1820, which named the group the Borodino Islands[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) |
| Settlement | 23 pioneer settlers from Hachijō Island landed on January 23, 1900[6](https://www.minamidaito-okinawa.com/about) |
| Access | About 1 hour by air from Naha (50-seat DHC8-Q400CC); 13 hours by ferry, one or two sailings a week[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) |
## Geography and geology
From the sea the island appears as a flat line on the horizon, but its interior is a ring of hills around a central basin, a shape that resembles a volcanic island without being one.[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) It is entirely a coral island: an atoll, a ring-shaped coral reef in the open ocean, that has been lifted out of the sea by several episodes of uplift.[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) The island is composed entirely of dolomite and limestone.[4](https://www.sciencedirect.com/science/article/pii/S2214581820301907)
The Daito Islands have an unusual tectonic history. They formed as coral reefs accumulating on a volcanic edifice near the equator about 50 million years ago and drifted northward on the Philippine Sea Plate; reef growth over thousands of years built limestone layers to a thickness of about 2,000 meters at the top of the structure.[7](https://www.jamstec.go.jp/dark/e/reports/20240329/) As the plate migrates toward the Ryukyu Trench, its flexure produces a slow up-bulging that raises the former atolls. The average uplift rate at Minami-Daito is about 0.05 m per thousand years, far below the roughly 1.8 m per thousand years measured at Kikai Island on the [Eurasian Plate](https://www.edgepedia.org/eurasian-plate), but sustained over at least several million years.[5](https://cir.nii.ac.jp/crid/1390001204229719168) • [8](https://www.sciencedirect.com/science/article/pii/104061829290033X) This slow, long-lived emergence defines what the geological literature calls the Daito-type of coral reef terrace development.[8](https://www.sciencedirect.com/science/article/pii/104061829290033X)
**Karst landscape.** Erosion of the thick limestone has produced more than 100 limestone caves on the island, the largest being Hoshino Cave, with stalagmites, stalactites, and fossilized coral; Akiba Chiteiko Cave contains a subterranean lake and requires a hired guide.[9](https://visitokinawajapan.com/destinations/okinawa-main-island/southern-okinawa-main-island/minami-daito-island/) The island also holds more than 100 small bodies of freshwater, including ponds at the island's center; the largest, Oike no Ohirugi Gunraku, is a freshwater lake with wild mangroves designated a Natural Monument.[9](https://visitokinawajapan.com/destinations/okinawa-main-island/southern-okinawa-main-island/minami-daito-island/) • [1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) Many ponds are linked by narrow waterways used for kayaking.[9](https://visitokinawajapan.com/destinations/okinawa-main-island/southern-okinawa-main-island/minami-daito-island/)
## Marine environment
The coast is a sheer precipice, and the surrounding sea floor drops fast: depths reach 1,000 m about 2 km from shore, and 98.7 percent of the 20.9 km of coast is natural.[2](https://www.env.go.jp/en/nature/biodic/kaiyo-hozen/kaiiki/engan/20901.html) The Ministry of the [Environment](https://www.edgepedia.org/environment) has designated the waters around the island as an Ecologically or Biologically Significant Marine Area, selected because rare species live there, including high concentrations of the rayed wheel limpet, a species found at few locations in Japan, and the snail Tectarius (Echininus) spinulosus, which may not be recorded anywhere else.[2](https://www.env.go.jp/en/nature/biodic/kaiyo-hozen/kaiiki/engan/20901.html) The fringing reefs are poorly developed compared with those of the main Ryukyu chain.[10](https://www.env.go.jp/nature/biodic/coralreefs/reference/contents/060105.pdf)
## History
The name Daito derives from the Okinawan island phrase "Ufuagarijima," meaning islands far across the eastern sea; Ryukyuan legend knew of an island at the eastern edge.[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) • [6](https://www.minamidaito-okinawa.com/about) The islands first appeared on European maps in the early 17th century, though with inaccurate positions and no certain discoverer.[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) In 1820 the Russian vessel Borodino, commanded by the naval officer Ponafidin, sighted the group, which then entered British Admiralty charts and Western maps as the Borodino Islands.[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html)
Okinawa [Prefecture](https://www.edgepedia.org/prefecture) took formal possession in 1885, when the island was uninhabited.[6](https://www.minamidaito-okinawa.com/about) Permanent settlement began on January 23, 1900, when 23 pioneer colonists from Hachijō Island, south of Tokyo, landed at the site of the present West Port.[6](https://www.minamidaito-okinawa.com/about) Human habitation therefore spans a little over a century on an island whose natural communities developed over millions of years, and the village promotes the island's untouched nature and endemic native plants and animals as its defining character.[11](https://www.vill.minamidaito.okinawa.jp/site/kankou/)
## Economy and access
Sugarcane is farmed extensively and is the staple crop, covering much of the island's interior plateau.[9](https://visitokinawajapan.com/destinations/okinawa-main-island/southern-okinawa-main-island/minami-daito-island/) The annual mean air temperature is 22.9 °C.[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html)
The island is reached by air and by sea. Flights connect [Naha Airport](https://www.edgepedia.org/naha-airport) with Minamidaito Airport in about one hour using a 50-seat DHC8-Q400CC aircraft.[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) The ferry Daito sails from Naha's Tomari Port once or twice a week (four or five sailings a month), taking 13 hours, with a one-way adult fare of 5,690 yen; sailings are subject to weather cancellations.[1](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html) The Okinawa travel guide describes the crossing as around 15 hours with about six ferry departures a month, a difference in published schedules between sources.[9](https://visitokinawajapan.com/destinations/okinawa-main-island/southern-okinawa-main-island/minami-daito-island/)
## References
1. [島の紹介, 南大東村移住定住サイト (Minamidaito Village)](https://www.vill.minamidaito.okinawa.jp/site/iju/377.html)
2. [Minami-Daitojima Island, Ecologically or Biologically Significant Marine Areas, Ministry of the Environment, Japan](https://www.env.go.jp/en/nature/biodic/kaiyo-hozen/kaiiki/engan/20901.html)
3. [Conservation paleobiology on Minami-Daito Island, Okinawa, Japan (PMC)](https://pmc.ncbi.nlm.nih.gov/articles/PMC8801181/)
4. [Hydrogeochemical processes and long-term effects of sea-level rise in an uplifted atoll island of Minami-Daito, Japan (ScienceDirect)](https://www.sciencedirect.com/science/article/pii/S2214581820301907)
5. [Late Quaternary Tectonic Movements as Deduced from Raised Coral Reefs of Daito Islands (CiNii Research)](https://cir.nii.ac.jp/crid/1390001204229719168)
6. [南大東島とは, 南大東村観光協会 (Minamidaito Tourism Association)](https://www.minamidaito-okinawa.com/about)
7. [Inspection of Minami Daito Island, D-ARK, JAMSTEC](https://www.jamstec.go.jp/dark/e/reports/20240329/)
8. [Contrasting styles and rates of tectonic uplift of coral reef terraces in the Ryukyu and Daito Islands, Quaternary International (ScienceDirect)](https://www.sciencedirect.com/science/article/pii/104061829290033X)
9. [Minami-Daito Island, VISIT OKINAWA JAPAN](https://visitokinawajapan.com/destinations/okinawa-main-island/southern-okinawa-main-island/minami-daito-island/)
10. [Coral Reefs of Japan, 6-1-5 Daito Islands, Ministry of the Environment](https://www.env.go.jp/nature/biodic/coralreefs/reference/contents/060105.pdf)
11. [南大東島観光スポット, 南大東村ホームページ](https://www.vill.minamidaito.okinawa.jp/site/kankou/)
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*Topic: Encyclopedia › Places and geography › Landforms and terrestrial features › Islands and dry-land coastal features › Islands and island geography of Asia › Japanese islands*
*Initially written Sep 17, 2026 · Reviewed: Sep 18, 2026; Sep 30, 2026; Oct 21, 2026 · Edited: Sep 18, 2026; Sep 30, 2026; Oct 21, 2026 · Last review: Oct 21, 2026*
*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*
License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license