San Francisco

A TUNNEL in Las Vegas that is nearly 1.5 km long and meant to showcase a "traffic busting" alternative for overcrowded cities should be completed next year, innovative entrepreneur Elon Musk said on Twitter.

The people-moving tunnel is being built by The Boring Company, one of several future-oriented enterprises founded by Mr Musk, along with the Tesla electric car company and SpaceX, which develops launch vehicles.

The 48-year-old billionaire tweeted late on Friday that "Boring Co is completing its first commercial tunnel in Vegas, going from Convention Center to Strip". In a second tweet, he said it would be "hopefully fully operational in 2020". The Las Vegas convention centre is a sprawling complex being further enlarged - the 1.3 km tunnel would facilitate travel within the center and to the city's famous Strip, where many of its major hotels and casinos are located.

Las Vegas officials selected The Boring Company in March to design, build and manage twin tunnels capable of transporting passengers in small, autonomous vehicles, each holding eight to 16 passengers.

The South Africa-born Mr Musk, who is known for original and sometimes fanciful thinking, has long advocated a futuristic underground train system, called the Hyperloop, that would allow passenger capsules on Tesla-built chassis to move through low-pressure tubes at high speeds.

He aspires eventually to build such a system linking Washington and New York along the busy US North-east corridor; he has also proposed projects for Chicago and Los Angeles.

Mr Musk's company last year showed reporters a new test tunnel in California, but Las Vegas is Boring's first paying customer.

The cost of the tunnel, originally estimated to be as low as US$35 million, has since risen to US$52.5 million, according to the Las Vegas Review-Journal newspaper.

Mr Musk hopes that Boring's people-moving technology will help revolutionise urban transit in an ever more crowded world. He said that the idea came to him as he sat in growing frustration in his car, stuck in a traffic jam between his pricey villa in Bel Air, California and the SpaceX offices in Hawthorne, south of Los Angeles.

He envisioned thousands of autonomous electric vehicles eventually moving millions of people underground at speeds up to 250 kmh - far higher than the moderate 56 kmh speeds planned for the short Las Vegas link. AFP