By Carlo Versano

Elon Musk's Boring Company will unveil its first completed segment of tunnel under Los Angeles on December 10, the CEO said in a series of late-night tweets Sunday.

The Hawthorne Tunnel, named for the area near LAX and SpaceX headquarters, is a "loop" that Musk envisions can carry cars, cyclists, and pedestrians on a platform at speeds up to 155 mph.

He tweeted that the Dec. 10 event would be followed by free rides to the public the following day. The Boring Company has proposed a fare of $1 per passenger to take the loop under L.A.

The Boring Company may have begun as a joke, but Musk now envisions it will solve traffic problems in urban areas with high-speed underground tunnels that use autonomous "skates" to move single vehicles and groups of commuters at speeds higher than would be allowed on expressways (though still not as fast as his Hyperloop concept, in which people would move as fast as 600 mph inside pods for longer distances inside a vacuum-sealed tube).

In addition to the L.A. tunnel, the company has a contract with the city of Chicago to build a similar loop to O'Hare and is in the planning stages for a loop between Washington D.C. and Baltimore. It's also proposing a loop from west L.A. to Dodger Stadium.

Musk, who has made a [habit] ( of tweeting promises he wasn't able to keep, responded to a user who asked whether the Dec. 10 schedule was "in real time or Elon time."

"I think real," he wrote.