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There's been a lot of talk about the border between the United Kingdom and Ireland in the wake of Brexit. For instance, the free movement of goods could be hindered after Britain leaves the European Union. As NPR's Eleanor Beardsley reports, the impact could be far greater for the U.K.'s border with France.
ELEANOR BEARDSLEY, BYLINE: Hundreds of trucks are idling in the northern French port of Calais, lining up to drive onto ferries. Some 2 million trucks a year cross the English Channel from here to Dover, the closest point between Britain and the continent. Another 2 million make the crossing by train through the Channel Tunnel. Calais port director Jean-Marc Puissesseau says the Calais-to-Dover route is the busiest trading corridor in Europe.
JEAN-MARC PUISSESSEAU: There is nowhere in Europe that there is so important traffic - rapid traffic. You know, that's the particularity of Calais - the very fast crossing, very fast registering.
BEARDSLEY: It's the speed of the crossing that's so important for fresh food, flowers and pharmaceutical imports. It's also vital for Britain's auto industry, which operates on what's called a just-in-time inventory with components arriving at the factory just as they're needed.
JEAN-PAUL MULOT: The cars are assembled in the U.K. They produce I think 2.2 million, you know, cars a year. But all the parts are coming from the continent. The fluidity at the border is essential. Every minute is a huge cost.
BEARDSLEY: That's Jean-Paul Mulot. He's a representative for the northern French region in Britain. Mulot says French and British officials are so concerned about preventing delays at the Channel crossing that they're working together at the local level to come up with their own proposals for the EU-U.K. negotiators in Brussels in case of different Brexit scenarios.
MULOT: To say, look; that could be a solution to maintain the fluidity in case of hard Brexit, in case of soft Brexit.
BEARDSLEY: British ministers are fighting amongst themselves over whether to stay in the Customs Union once Britain leaves the EU. Pauline Bastidon of Britain's Freight Transport Association says any change in the current system could cause massive delays at the Channel border.
PAULINE BASTIDON: If you just stop - I don't know - 3 percent, for instance, of the more than 10,000 vehicles you have today, I mean, as you can imagine, it would already start creating delays.
KARAN BILIMORIA: You literally have millions of lorries a year going through Calais, going through the Channel Tunnel seamlessly. Just a 2 minutes check per vehicle would mean a tailback of lorries from Dover almost all the way back to London and, similarly at the other end in France, a tailback of well over 15 miles.
BEARDSLEY: Back in the port of Calais, I climb up into the cab of Polish trucker Andrei Ordon.
He's been driving for more than 30 years and remembers how things were done before the European Union.
ANDREI ORDON: I remember time when I drove to different country and, you know - stopped, checked seals, documents, CMRs.
BEARDSLEY: Ordon says he can't imagine going back to those days. Eleanor Beardsley, NPR News, Calais. Transcript provided by NPR, Copyright NPR.