Two years after he first announced his plan to avoid traffic and make public transportation more efficient, Musk and his Boring Company are set to open their first test tunnel tonight and reveal the autonomous vehicles that will travel through it at speeds up to 155 mph. The test tunnel is in Hawthorne, Calif., and runs about two miles from the headquarters of SpaceX, another Musk venture.

The launch was originally planned for December 10, but was delayed. Musk tweeted that the opening would feature “modded but fully road legal autonomous transport cars,” as well as “ground to tunnel car elevators.” In addition, the company is building a medieval-style tower out of the dirt excavated for the tunnel, and actors in medieval attire will attend the launch.

In November, Musk posted a time-lapse video of the length of the tunnel on Twitter, calling it “disturbingly long.” The two-mile tunnel in southern California is a proof of concept for what Musk says will be a revolution in the way we travel. He has gained approval to build a tunnel that will take riders from downtown Chicago to O’Hare airport in 12 minutes, and he says it’ll cost no more than a bus ticket.

But not everyone agrees that Musk’s tunnels are the way forward. Residents near another Los Angeles area test tunnel successfully got the Boring Company to stop boring over environmental concerns.

If you can’t make it to Hawthorne, there will be a live webcast of the opening starting at 8 p.m. P.T.