Hyperloop might become a reality sooner than we thought: Elon Musk said he will be building a test track.

Musk, who’s been talking about his high-speed train-in-a-tube for quite some time, announced the news in a tweet:

Shortly after, he tweeted an additional idea:

Musk first unveiled his Hyperloop idea in the summer of 2012, in a 57-page long document detailing how the high-speed train will work. At the time, he said he wouldn’t be building it, though a test track now seems to be on his to-do list.

Texas, Musk’s tentative location for the test track, is also where SpaceX’s new launch site will be.