In anticipation of the developments, the entire area (947 acres; 383 ha) was annexed by the city of Tukwila in November 1957. Southcenter Corporation strategically purchased  at what would eventually become the intersection of two major freeways, the Seattle-Tacoma Freeway (I-5) and I-405. The construction schedule of the mall was dependent on the construction of the freeways.
To prepare for future developments, the entire area was annexed by Tukwila in November 1957. Southcenter Corporation purchased land strategically at a location where two major freeways would intersect (I-5 and I-405), which influenced the mall's construction timeline.