Geography in Indonesia

Indonesia is an archipelagic island country in Southeast Asia, lying between the Indian Ocean and the Pacific Ocean. It is in a strategic location astride or along major sea lanes from Indian Ocean to Pacific Ocean. The country's variations in culture have been shaped—although not specifically determined—by centuries of complex interactions with the physical environment. Although Indonesians are now less vulnerable to the of nature as a result of improved technology and social programs, to some extent their social diversity has emerged from traditionally different patterns of adjustment to their physical circumstances.

The archipelagic country extending 5,120 kilometers from east to west and 1,760 kilometers from north to south. It encompasses and estimated 17,508 islands, only 6,000 of which are inhabited.
Indonesia's total land area is 1,919,317 square kilometers. Included in Indonesia's total territory is another 93,000 square kilometers of inland seas (straits, bays, and other bodies of water). The additional surrounding sea areas bring Indonesia's generally recognized territory (land and sea) to about 5 million square kilometers.

Generally the archipelago is grouped including Sumatra, Java (and Madura), Kalimantan (in Borneo island), and Sulawesi in the Greater Sunda Islands. These islands, except for Sulawesi, lie on the Sunda Shelf—an extension of the Malay Peninsula and the Southeast Asian mainland. At Indonesia's eastern extremity is Papua, which takes up the western half of the world's second largest island--New Guinea--on the Sahul Shelf.

Mountains ranging between 3,000 and 3,800 meters above sea level can be found on the islands of Sumatra, Java, Bali, Lombok, Sulawesi, and Seram. The country's tallest mountains are located in the Jayawijaya Mountains and the Sudirman Mountains in Papua. The highest peak, Puncak Jaya, also known as Mount Carstenz, which reaches 4,884 meters, is located in the Sudirman Mountains.
Nusa Tenggara consists of two strings of islands stretching eastward from Bali toward Papua. The inner arc of Nusa Tenggara is a continuation of the chain of mountains and volcanoes extending from Sumatra through Java, Bali, and Flores, and trailing off in the Banda Islands. The outer arc of Nusa Tenggara is a geological extension of the chain of islands west of Sumatra that includes Nias, Mentawai, and Enggano. This chain resurfaces in Nusa Tenggara in the ruggedly mountainous islands of Sumba and Timor.