Between taking SpaceX public in the largest IPO on record and rolling out a fleet of driverless Tesla Cybercabs in Austin, Texas, Elon Musk has also been digging tunnels. His tunneling venture, The Boring Co. announced late Wednesday that it’s now valued at $23 billion.

Created inside SpaceX in 2017 and spun out a year later, The Boring Co. says its aim is to “revolutionize transportation” by creating underground loops with stations where passengers can board and exit.

While Boring Co. has announced about a dozen city projects, its only loop for public use today is in Las Vegas, where passengers can travel in Tesla vehicles between the downtown convention center and various casino resorts via its Las Vegas Convention Center (LVCC) Loop.

In July of last year, Boring Co. also reached a deal to build 20 miles of tunnels in Nashville, Tennessee, a project dubbed the Music City Loop, to carry paying passengers between downtown and the airport in Tesla vehicles.

The fast-tracked project sparked a partisan feud, and a survey by Vanderbilt University in March found that most Nashville residents didn’t want the tunnels in their city. A month before the survey, the company broke ground in Nashville, and it shared clips this week showing its Prufrock machines digging into the city’s limestone geology.

With the latest financing, Boring Co. has reeled in an additional $3 billion in a round led by the United Arab Emirates, where the company plans to build over 150 kilometers (93 miles) of tunnels, including a project announced in February of last year, the Dubai Loop.

To finance the costly endeavors, Musk has turned to many of the same investors that previously backed Tesla, SpaceX, and his buyout of Twitter in 2022. Those investors include Valor Equity Partners, Sequoia Capital, Andreessen Horowitz, Singapore’s Temasek and Baron Capital.

As with his other companies, where Musk’s grand promises have sometimes failed to materialize, many of Boring Co.’s plans have fizzled. In 2018, the company abandoned tunnel projects it had pursued in Los Angeles, with others in Chicago and the Washington, D.C. area never coming to fruition.

Earlier this year, Boring Co. ran a contest, the Tunnel Vision Challenge, promising winners a “free” one-mile tunnel. The Baltimore Ravens, who had entered the challenge and won, turned down Musk’s offer after initial meetings with the company.

Some communities are hesitant to work with Musk’s company due to its safety and environmental track record. In Las Vegas, Boring Co. racked up hundreds of environmental violations, ProPublica reported, with additional workplace safety and environmental violations in its home state of Texas.

Boring Co. didn’t respond to a request for comment.

The company sees plenty of opportunities for growth, including expansion plans underway in Las Vegas.

“Over the past two years, The Boring Company has grown from a single operating Loop system to a multi-city tunneling program, pairing faster machine design with the first hard-rock project, the first international construction contract, and a substantial expansion of Vegas Loop,” the company wrote in its post on Wednesday about fundraising.

Following the announcement, Musk posted on X, “Congrats Boring Company team!”

In June, the company won approval from the Nevada System of Higher Education to build a station at the University of Nevada Las Vegas campus, and it’s working to extend the reach of its Vegas Loop to the airport and to Allegiant Stadium, where the NFL’s Raiders play.

The Boring Co.’s growing ambitions are a potential boon for Tesla. The companies have worked together for years, with Tesla paying Boring Co. about $1 million in 2025 to dig a “Cybertunnel” under its Austin Gigafactory, connecting a Cybertruck assembly line to a lot for loading the vehicles. Tesla vehicles are used to shuttle passengers between Boring Co.’s stations.

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