A developer is completing plans to add 31 acres of mixed-use development in the heart of Merrifield, part of what may become a new network of urban cores in Fairfax, Northern Virginia’s largest suburban county.

South Carolina-based Edens and Avant is planning about 600,000 square feet of retail, 800,000 square feet of residential area, 150,000 square feet of office space, as well as a cinema and hotel on about 31 acres close to the intersection of Lee Highway and Gallows Road.