This week’s Series C funding round values the startup at $5.675 billion and was led by the venture capital firms Vy Capital and Sequoia Capital, with help from Valor Equity Partners, Founders Fund, 8VC, Craft Ventures, and DFJ Growth.

“Please consider working at the Boring Company! Our goal is to solve traffic, which plagues every major city on Earth,” Musk wrote on Wednesday after the funding announcement.

The Boring Company, which was founded by Musk in 2016, hopes to “revolutionize transportation” by creating a network of underground tunnels to transport cargo and passengers.

Thus far, the Austin-based startup hasn’t revolutionized public transportation, but it has managed to build two operational tunnels: one underneath the Las Vegas Convention Center and one 1.1-mile test tunnel in Hawthorne, Calif. 

The Boring Company has also received approval to create its first public transportation system in Las Vegas, which will consist of 29 miles of tunnel and 51 passenger stations. The company claims the system will eventually be able to transport some 57,000 passengers per hour. 

Boring Company management says it will use proceeds of its latest funding round to “significantly increase hiring across engineering, operations, and production” and build out the new system.

The startup uses a giant machine called a Prufrock to dig its tunnels underground. Thus far, the digger is only able to create around one mile of track per week, but Musk and company say their next version of the Prufrock will manage to bore seven miles of tunnel per day.

It’s another lofty claim in a long line of false promises from the Boring Company, however. When Musk first announced his plans to start boring tunnels for public transportation, he had high hopes that a loop system was going to carry 16-passenger electric vehicles at 155 miles per hour. But on Las Vegas test tracks under the convention center, the Boring Company managed to move Tesla EVs through the tunnels at only around 40 miles per hour.

The Boring Company had also promised to build underground transportation systems in Los Angeles, Chicago, and Baltimore, but those projects stalled before digging began, and the company’s website no longer mentions operations in those cities.

In 2017, Musk announced on Twitter that he had “received verbal govt approval for The Boring Company to build an underground NY-Phil-Balt-DC hyperloop.” The Tesla CEO claimed the tunnel would allow for a 29-minute trip between D.C. and New York—but once again, the project has been dropped and now doesn’t appear on the Boring Company’s website.