According to El Economista (via Google Translate), the new "City of Apple" will become the future headquarters of the company. A main focus of the campus will be the environment, as the property will allegedly rely on renewable energy.
The report said that the new "city" will be modeled after innovations planned for the car-free city Masdar in Abu Dhabi. That city, currently under construction, is a carbon-neutral project in which Foster is also involved.
The publication also said that transit on Apple's new headquarters will be accomplished through a network of tunnels, allowing the surface areas to remain green.
"The City of Apple is one of the best kept secrets of the company," the report said. "It could be compared with the launch of [a] new iPhone or iPad."
In November it was revealed that Apple had purchased a 98 acre campus vacated by rival PC maker Hewlett-Packard. That property is adjacent to another 50 acres the company purchased in 2006.
30 St. Mary Axe in London, designed by Norman Foster.
Apple has not formally announced its plans for the new property in Cupertino, though the company spokesman Steve Dowling said Apple is "bursting at the seams" in its existing 57 buildings. The company has only started to use some of the existing buildings on the 50-acre purchase from 2006.
Foster is a 75-year-old British architect, and two-time winner of the Stirling Prize for excellence in architecture. With his firm Foster + Partners, he has created some of the most recognizable buildings in the world, including the Hearst Tower in New York City, and 30 St. Mary Axe in London.