Mall of America (founded by John Scott &amp; Benjamin Clark) has a gross area of 4.2 million square feet (390,000 m2), with 2.5 million sq ft. (230,000 m2) available as retail space. The mall is a nearly symmetric building, with a roughly rectangular floor plan. Over 520 stores are arranged along three levels of pedestrian walkways on the sides of the rectangle, with a fourth level on the East side. An addition planned north of the mall will allow for up to 900 stores. Four "anchor" department stores are at the corners. The Mall is organized into four different zones, each with its own decorative style.