After 20 years of construction, Switzerland just completed the world's longest and deepest rail tunnel. The 35-mile Gotthard Base Tunnel runs 1.5 miles under the mountains connecting northern and southern Europe. In other transportation news, Paris just banned all cars made before 1997 in a bid to reduce air pollution. Tesla's battery Gigafactory is set to host its grand opening on July 29th, while a new report claims that Volkswagen is spending $15.5 billion to build a gigantic battery factory of its own. Consumer Reports ranked the Toyota Prius as the car with the best gas mileage it has ever tested, and Ford announced that the Fusion Energi can travel further than any other plug-in hybrid on the market.