Planners of the 2012 London Olympics say they have chosen two design companies to create public spaces that will welcome visitors to the Olympic Park.

Two competitions were held to select the firms, which were asked to come up with plans for a visitor center, a playground, and a 50-acre landscape that links the Olympic Stadium, Aquatics Center and a landmark sculpture called the "ArcelorMittal Orbit."

New York-based James Corner Field Operations won with its design, a tree-lined promenade that will welcome visitors to the Park, while London-based Erect Architecture was chosen for its design of a community hub building north of the Park.

London Mayor Boris Johnson said Tuesday the public spaces will be at the heart of new communities that will develop in the area.