European route E40

European route E40 is the longest European route, more than 8,000 kilometres long, connecting Calais in France via Belgium, Germany, Poland, Ukraine, Russia, Kazakhstan, Uzbekistan, Turkmenistan, and Kyrgyzstan, with Ridder in Kazakhstan near the border with Russia and China.A different route connecting Calais and Ridder is about 2,000 kilometres shorter, mostly using the E30 via Berlin-Moscow-Omsk. The E40 differs from that route in order to provide additional direct east-west access to Uzbekistan, Turkmenistan, and Kyrgyzstan, which have a combined population base approaching 50 million people as of 2021.

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