The 728-foot vessel will offer 39 luxury residences and “seven-star” service

The largest yacht in the world, at 728 feet, is underway in Norway, the ship’s designer, VARD, announced on Monday.

The enormous, 33,500-ton “yacht liner,” dubbed Somnio, will contain a collection of 39 luxury apartments, with Tillberg Design of Sweden and Winch Design from the U.K. creating the residences and amenity spaces.

“Somnio, meaning ‘to dream’ in Latin, will be the largest yacht in the world by length and volume, and offer apartment owners the finest quality available at sea,” Captain Erik Bredhe, co-founder of Somnio, said in a statement. “We are really looking forward to seeing this beautiful yacht liner sail in 2024.”

Residences will be spread over six decks and are fully customizable, with options like private outdoor space, libraries, chef’s kitchens and dressing rooms. Prices start at €9.5 million (US$11.2 million) and sales are by invitation only, but serious buyers know how to get in touch, according to a spokesman for the project. Some units have already sold, he added, but declined to give additional details.

The yacht will offer “seven-star” service to its residents, as well as access to some of the world’s finest ports. That includes the Mediterranean, New York, the South Pacific and expeditions in Antarctica, according to the launch brochure.

“Owners will share a truly unique lifestyle at sea, with a hand-picked crew and a never-ending global itinerary of carefully selected destinations and experiences befitting a yacht of this nature,” Mr. Bredhe said in a separate statement released by Winch Design.

Amenities will include a 10,000-bottle wine cellar and tasting room, several restaurants and bars, an onboard beach club with water-sports facilities, several pools and a lounge in the ship’s bow to give people a “spectacular” vantage point when entering and leaving ports around the world, according to Winch Design.

Sustainability and ocean research will also be key to Somnio, which will employ the latest clean engine technology and onboard equipment to aid marine scientists in their research, according to Winch. Jim Dixon, director of yachts and aviation at Winch Design called the project a “revolutionary landmark for the industry.”

The project, which will be delivered from Vard Søviknes in Norway, is expected to take about three years.

“We are really looking forward to seeing this beautiful yacht liner sail in 2024,” Mr. Bredhe said.