the trans-asian railway (tar) is a project to create an integrated freight railway network across europe and asia. the tar is a project of the united nations economic and social commission for asia and the pacific (unescap). == overview ==  the project was initiated in the 1960s, with the objective of providing a continuous  rail link between singapore and istanbul, turkey, with possible further connections to europe and africa. at the time shipping and air travel were not as well developed, and the project promised to significantly reduce shipping times and costs between europe and asia. progress in developing the tar was hindered by political and economic obstacles throughout the 1960s, 1970s and early 1980s. by the 1990s, the end of the cold war and normalisation of relations between some countries improved the prospects for creating a rail network across the asian continent. the tar was seen as a way to accommodate the huge increases in international trade between eurasian nations and facilitate the increased movements of goods between countries. it was also seen as a way to improve the economies and accessibility of landlocked countries like laos, afghanistan, mongolia, and the central asian republics. much of the railway network already exists as part of the eurasian land bridge, although some significant gaps remain. a big challenge is the differences in rail gauge across eurasia. four different major rail gauges (which measures the distance between rails) exist across the continent: most of europe, as well as turkey, iran, china, and the koreas use the  gauge, known as standard gauge; russia, and the former soviet republics use a  gauge; finland uses a  gauge; most of the railways in india, pakistan, bangladesh and sri lanka use the  gauge, known as indian gauge; and most of southeast asia has  gauge. for the most part the tar would not change national gauges; mechanized facilities would be built to move shipping containers from train to train at the breaks of gauge. by 2001, four corridors had been studied as part of the plan: * the northern corridor will link europe and the pacific, via germany, poland, belarus, russia, kazakhstan, mongolia, china, and the koreas, with breaks of gauge at the polish-belarusian border ( to ), the kazakhstan-chinese border and the mongolian-chinese border (both  to ). the  trans-siberian railway covers much of this route and currently carries large amounts of freight from east-asia to moscow and on to the rest of europe. due to political problems with north korea, freight from south korea must currently be shipped by sea to the port of vladivostok to access 
International_rail_transport Proposed_transport_infrastructure_in_Asia Rail_transport_in_Asia