 indonesia's transport system has been shaped over time by the economic resource base of an archipelago with thousands of islands, and the distribution of its more than 200 million people highly concentrated on a single island which is java.indonesia's diversity revisited http://cip.cornell.edu/dienst/ui/1.0/summarize/seap.indo/1107012385 all transport modes play a role in the countryâs transport system and are generally complementary rather than competitive. road transport is predominant, with a total system length of 437,759&nbsp;km in 2008. the railway system has four unconnected networks in java and sumatra primarily dedicated to transport bulk commodities and long-distance passenger traffic. sea transport is extremely important for economic integration and for domestic and foreign trade. it is well developed, with each of the major islands having at least one significant port city. the role of inland waterways is relatively minor and is limited to certain areas of eastern sumatra and kalimantan. the function of air transport is significant, particularly where land or water transport is deficient or non-existent. it is based on an extensive domestic airline network where all major cities can be reached by passenger plane. ==merchant marine vessels== thumb|300px|pelni shipping routes 2006  thumb|right|port of merak, the main port from banten, java to lampung, sumatera. because indonesia encompasses a sprawling archipelago, maritime shipping provides essential links between different parts of the country. boats in common use include large container ships, a variety of ferries, passenger ships, sailing ships, and smaller motorized vessels. traditional wooden vessel pinisi still widely used as the inter-island freight service within indonesian archipelago. main pinisi traditional harbours is sunda kelapa in jakarta and paotere harbour in makassar. frequent ferry services cross the straits between nearby islands, especially in the chain of islands stretching from sumatra through java to the lesser sunda islands. on the busy crossings between sumatra, java, and bali, multiple car ferries run frequently twenty-four hours per day. there are also international ferry services between across the straits of malacca between sumatra and malaysia, and between singapore and nearby indonesian islands, such as batam. a network of passenger ships makes longer connections to more remote islands, especially in the eastern part of the archipelago. the national shipping line, pelni, prov
Infrastructure_in_Indonesia Transport_in_Indonesia