At a shipyard in the Netherlands—the world’s megayacht maternity ward—the largest vessel of its kind is being custom-built for Amazon.com Inc. founder Jeff Bezos at a projected cost that tops $500 million. With more than 400 feet of sleek aluminum and steel, it will join an elite new vessel category: the gigayacht.

The pandemic has intensified the desire to bubble oneself away from the world and widened the wealth gap further, making Bezos merely the latest business magnate fancying a life at sea (when he’s not in space).