If Elon Musk is going to announce news, there’s a good chance he’ll do it on Twitter. Thursday morning he made an announcement on the social media site about a new Boring tunnel project that would connect the cities of New York, Philadelphia, Baltimore and Washington D.C. He tweeted to his 10.3 million followers that he has received “verbal govt approval for The Boring Company” to build an underground hyperloop connecting the four East-coast cities.

The travel time from New York to D.C. would take 29 minutes, Musk included in his tweet. He also followed up noting that it would connect “city center to city center” and that there would be a dozen or more entrances and exits in each city.

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Musk started the Boring Company last year to build tunnels that would connect cities and enable rapid transportation and relieve traffic. The company has already begun its first project, tunneling under Los Angeles. A mock video released in April shows a Tesla vehicle traveling underground on a platform and then speeding through tunnels on a skate, encountering no traffic, until it reaches its destination.

But Musk’s tweet says that the “verbal govt approval” was for an underground hyperloop. The hyperloop technology does not involve cars traveling through underground tunnels but rather "pods" full of passengers. The extreme rapid transportation system would be kind of like a super high speed underground train. This technology is what would allow for that 29 minute travel time to cover the nearly 250 miles between New York and D.C.

But don't start packing your bags quite yet take a quick trip to one of these cities. "Verbal govt approval" doesn't mean this project is definitely happening, in other words Musk won't be breaking ground for a while.

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Thursday, a BBC reporter tweeted that the announcement seemed premature, unless the SpaceX and Tesla CEO was trying to drum "up support for the project." Musk responded saying "Support would be much appreciated!" but did not reply when the same reporter asked who gave the verbal approval.

A transportation reporter for the Los Angeles Times also responded to Musk, asking which government approved the plan. The hyperloop would pass through multiple states meaning there would likely be a unique approval process in each state, something that would warrant more than "verbal" approval. Musk did not reply to this tweet either.

One USA Today reporter reached out to the New York Metropolitan Transportation Authority about Musk's tweet and said the press aide there was "flabbergasted."

For now if you want to take a trip to one of these cities you may have to just commit to traffic and public transportation. Although Musk is hopefully that he will get formal approval "rapidly" he said in a tweet about an hour and a half after he announced the verbal approval.