Musk showed a demonstration of the idea on stage, claiming that it will allow passengers to take “most long distance trips” in just 30 minutes, and go “anywhere on Earth in under an hour” for around the same price of an economy airline ticket.

In SpaceX’s video that illustrates the idea, passengers take a large boat from a dock in New York City to a floating launchpad out in the water. There, they board the same rocket named BFR (Big F**king Rocket) that Musk wants to use to send humans to Mars by 2024. But instead of heading off to another planet once they leave the Earth’s atmosphere, the ship separates and breaks off towards another city — Shanghai.

Details of how Musk plans to execute this was sketchy such a how many people per trip the rocket can load, how much of the air travel market Musk sees this occupying, how it would be regulated, or even when SpaceX might attempt such a feat.

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