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On Thursday, Elon Musk announced that he's secured "verbal government approval," whatever that is, to build a Hyperloop linking Washington DC to New York City, stopping in Baltimore and Philadelphia on the way. The Hyperloop system would travel in a tunnel dug by Elon Musk's new Boring Company, and Musk claims that it would do DC to New York in 29 minutes.

Hyperloop is Elon Musk's design for a semi-vacuum-tube electromagnetic transportation system. It consists of passenger (or car)-carrying pods that travel in a low-pressure tube. Musk announced the design two years ago, but released the plans for free as he claimed that he was too busy to pursue it.

Since then, numerous groups have sprung up to explore the technical challenges of the Hyperloop system. But the biggest obstacle that's been identified is getting the land. Due to the speeds of Hyperloop, it needs to travel in a virtually straight line, and it's impossibly difficult to buy enough land to travel in a straight line through built-up areas.

So, for the last year, Musk has been exploring the possibility of digging tunnels. He's been experimenting with tunnel digging in California, and founded the dad-joke-worthy "Boring Company," which was supposed to be solving LA's traffic problems by putting highways underground.

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But Musk's announcement today is ambitious on a whole new scale. High-speed-rail linking the cities of the northeast has been talked about for decades, but Musk sounds like he wants to make it a reality.

Now, a tweet claiming "verbal government approval" is not official by any means, and it could just be the result of a garbled phone call between Musk and Trump. But it's still a major statement of intent to undertake what would be the biggest infrastructure project in a generation.