European route E40 (E40) is a European route connecting Calais in France with Ridder in Kazakhstan near the border with Russia and China. 8,641 kilometres long, it is the longest route in the International E-road network. A different route, connecting Calais and Ridder, is about 2,000 kilometres shorter, mostly using the E30 via Berlin, Moscow, and Omsk. The E40 differs from that route in order to provide additional direct east–west access to Uzbekistan, Turkmenistan, and Kyrgyzstan, with a combined population base approaching 50 million people as of 2021.