Tech billionaires who have built their own private cities

Owning global companies is common for tech billionaires, but building entire cities or owning vast private territories takes ambition to a different level.

From Hawaiian islands and Texas company towns to floating seasteads and smart-city projects, Silicon Valley’s big names are reimagining what urban living might look like.

Here are some of the most ambitious projects led by the world’s richest innovators.

Elon Musk

Tesla and SpaceX CEO Elon Musk has built two towns in Texas. Starbase, formerly Boca Chica, now serves as SpaceX’s launch site and community, while Snailbrook near Bastrop houses Tesla and SpaceX employees.

Both include housing, schools, and manufacturing hubs. Musk envisions these as stepping stones toward his ultimate goal: a self-sustaining city on Mars.

Larry Ellison

Oracle co-founder Larry Ellison, who recently surpassed Musk as the world’s richest person with a net worth of about $393 billion, owns 98% of Lanai, Hawaii’s sixth-largest island.

Since acquiring it in 2012 for $300 million, Ellison has tried to turn it into a model of sustainability, complete with luxury resorts and renewable energy initiatives.

He also owns the island’s two Four Seasons hotels, most commercial properties, and serves as landlord to the majority of residents

Peter Thiel

PayPal co-founder Peter Thiel backed the idea of “seasteading,” floating cities beyond government control.

Though the concept stalled, Thiel now supports Praxis, a proposed libertarian-minded “startup city” eyeing Greenland as a base. 

The plan focuses on AI and minimal corporate regulation, but progress remains slow.

Bill Gates

In 2017, Microsoft co-founder, Bill Gates, invested in Belmont, a proposed smart city near Phoenix, Arizona.

This city is designed to house 180,000 residents with autonomous cars and high-speed infrastructure. 

Mark Zuckerberg

Meta CEO Mark Zuckerberg is building a $270 million compound on 2,300 acres in Kauai, Hawaii. 

Known as Ko‘olau Ranch, it will include mansions, dozens of buildings, farmland, and even a 5,000-square-foot underground bunker with its own escape tunnel.

While it’s not technically its own city, it will house more than a dozen buildings boasting upwards of 30 bedrooms and 30 bathrooms.