Discovery Channel ★ MegaStructures UK Super Train ★ National Geographic Documentary

The international definition of high-speed rail embraces new lines with a top speed of at least 250 km/h (155 mph) and existing lines with a top speed of aro.

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The international definition of high-speed rail embraces new lines with a top speed of at least 250 km/h (155 mph) and existing lines with a top speed of around .

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