The Trans-Siberian Railway has trip from Moscow in the far west of Russia to Viadvestok in far eastern part.The trip is 10,000 Kilometers or about 6214 Miles.

1) "The first Eurasian transcontinental railroad was the Trans-Siberian railway (with connecting lines in Europe), completed in 1905 which connects Moscow with Vladivostok on the Pacific coast. There are two connections from this line to China. It is the world's longest rail line at 9,289km (5,772 miles) long. This line connects the European Railroad System with China, Mongolia and Korea. Since the former Soviet Countries and Mongolia use a broader gauge, a break of gauge is necessary either at the Eastern frontiers of Poland, Slovakia, Hungary and Romania or the Chinese border. In spite of this there are through services of passenger trains between Moscow and Beijing or through coaches from Berlin to Novosibirsk. Almost every major town along the Trans-Siberian railway has its own return service to Moscow." Source and further information: http://en.wikipedia.org/wiki/Transcontinental_railroad#Eurasia 2) "It may not be the longest train journey in the world, a record currently held by the 9,288.2 km (5,787 miles) Trans-Siberian Railway." Source: http://edition.cnn.com/2006/TRAVEL/03/04/ultimate.train/index.html 3) "The Trans-Siberian railway is often associated with the main transcontinental Russian train that connects hundreds of big and small cities of the European and Asian parts of Russia. At 9,288 kilometres (5,772 miles), spanning eight time zones and taking several days to complete the journey, it is the third-longest single continuous service in the world, after the Moscow–Pyongyang (10267 km, 6380 mi) and the Kiev–Vladivostok (10267 km, 6380 mi) services, both of which also follow the Trans-Siberian for much of their routes. The route was opened by Tsarevich Nicholas Alexandrovitch of Russia after his eastern journey ended." Source and further information: http://en.wikipedia.org/wiki/Trans-Siberian_Railway Further information: http://www.traintrips.explorertravel.co.uk/

From an advertisement in 2006 for the world's longest train trip ever: On Board: The Trans-Siberian Express Date: September,2006 Covering: 6,135 miles � from the Sea of Japan to the Kremlin (Russia) Tickets: Start at $8,695 a person based on double occupancy. At least that is their claim.