Nearly a decade ago, billionaire Peter Thiel cofounded a nonprofit called Seasteading Institute and contributed seed funding toward what could become the world's first floating city.

In May 2018, the institute embarked on a pilot project with the government of French Polynesia. The group plans to build 300 houses on an island, which will run under its own governance and use its own cryptocurrency called Varyon by 2022.

On Thursday, presales began for the Varyon cryptocurrency, offering bonuses from 5% to 15%. The presale will last until July 14. (The Seasteading Institute has not yet determined when the public sale will start.)

At first, the project's founders imagined the city as a libertarian utopia free of regulation (and taxes). Joe Quirk, president of the Institute, told Business Insider that his team's vision has evolved beyond that. The group now also sees the city as a way to live with rising sea levels, which are expected to increase more than six feet by the end of this century.

Take a look at the ambitious plan below.