is a geographic division of Japan refers to the islands of Ryukyu Islands

Ryukyu Islands

The , also known as the , is a chain of islands in the western Pacific, on the eastern limit of the East China Sea and to the southwest of the island of Kyushu in Japan. From about 1829 until the mid 20th century, they were alternately called Luchu, Loochoo, or Lewchew, akin to the Mandarin...

 under administration of Okinawa Prefecture

Okinawa Prefecture

is one of Japan's southern prefectures. It consists of hundreds of the Ryukyu Islands in a chain over long, which extends southwest from Kyūshū to Taiwan. Okinawa's capital, Naha, is located in the southern part of Okinawa Island...

.

The Okinawa Prefecture is an archipelagic

Archipelago

An archipelago , sometimes called an island group, is a chain or cluster of islands. The word archipelago is derived from the Greek ἄρχι- – arkhi- and πέλαγος – pélagos through the Italian arcipelago...

 island prefecture.

Major islands

The set of islands belonging to the prefecture is called Ryūkyū Shotō (琉球諸島). Okinawa's inhabited islands are typically divided into three geographical archipelagos. From northeast to southwest:

• • Ie-jima
  • Kume
  • Okinawa Island
    Okinawa Island
    Okinawa Island is the largest of the Okinawa Islands and the Ryukyu Islands of Japan, and is home to Naha, the capital of Okinawa Prefecture. The island has an area of...
    
    
  • Kerama Islands

• Miyako Islands
  Miyako Islands
  The are a group of islands in Okinawa Prefecture, Japan, east of the Yaeyama Islands.-Islands grouping:*Japanese Archipelago**Nansei Islands***Ryūkyū Shotō****Sakishima Islands*****Miyako Islands-Inhabited islands:*Miyako Islands...
  
  
  • Miyako-jima
    Miyako-jima
    Miyakojima is the largest and the most populous island among the Miyako Islands of Okinawa Prefecture, Japan. It lies approximately 400 kilometres east of Taipei, Taiwan...
    
    

• Yaeyama Islands
  Yaeyama Islands
  The Yaeyama Islands are a group of islands in Okinawa Prefecture, Japan.The isles are the remotest part of Japan from the main islands and contains Japan's most southern and most western inhabited islands.The islands form the southern part of the volcanic Nansei Islands...
  
  
  • Iriomote
    Iriomote
    Iriomote is the largest of the Yaeyama Islands and the second largest in Okinawa Prefecture after Okinawa Island itself....
    
    
  • Ishigaki
    Ishigaki
    *Ishigaki Island*Ishigaki, Okinawa*Ishigaki Airport*Japanese escort Ishigaki*Ai Ishigaki , guitarist for The Mad Capsule Markets*Ishigaki Rin...
    
    
  • Yonaguni
    Yonaguni
    is one of the Yaeyama Islands. It is the westernmost inhabited island of Japan and lies from the east coast of Taiwan, between the East China Sea and the Pacific Ocean proper....
    
    

• Senkaku Islands
  Senkaku Islands
  The , also known as the Diaoyu Islands or Diaoyutai Islands or the Pinnacle Islands, are a group of disputed uninhabited islands in the East China Sea...
  
   (disputed)

Geology

The island is largely composed of coral

Coral

Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...

, and rainwater filtering through that coral has given the island many cave

Cave

A cave or cavern is a natural underground space large enough for a human to enter. The term applies to natural cavities some part of which is in total darkness. The word cave also includes smaller spaces like rock shelters, sea caves, and grottos.Speleology is the science of exploration and study...

s, which played an important role in the Battle of Okinawa

Battle of Okinawa

The Battle of Okinawa, codenamed Operation Iceberg, was fought on the Ryukyu Islands of Okinawa and was the largest amphibious assault in the Pacific War of World War II. The 82-day-long battle lasted from early April until mid-June 1945...

. Gyokusendo is an extensive limestone cave in the southern part of Okinawa's main island.

Climate

The island experiences temperatures above 20 °C (68 °F) for most of the year. Okinawa and the many islands that make up the prefecture contains some of the most abundant coral reefs found in the world. Rare blue corals are found off of Ishigaki and Miyako islands as are numerous species throughout the chain.