“We have no idea what we’re doing,” declared Elon Musk, standing beside a yawning “test trench” in Southern California in 2017. A crowd of engineering students and tech reporters hooted and hollered, ...

Add Yahoo as a preferred source to see more of our stories on Google. Photo Credit: iStock Elon Musk has been intermittently focused on building underground Tesla tunnels for nearly a decade.

How Elon Musk’s Sci-Fi Hyperloop Failed Before his misadventures in government efficiency, Musk promised to revolutionize commuting with a subway that would speed passengers between DC and Baltimore ...