The sprawling, south Denver shopping complex, soon after its dedication in 1968. It was promoted as "the largest enclosed shopping center west of the Mississippi." At the time, the largest mall east of the Mississippi was Long Island's newly-enclosed ROOSEVELT FIELD.
Photo from Englewood Public Library / Mall History / Joshua Goldstein

THE LARGEST SHOPPING MALLS IN THE UNITED STATES, 1968:

1. ROOSEVELT FIELD MALL [1,485,000 sf], Nassau County, NY
2. CINDERELLA CITY [1,350,000 sf], Englewood, CO
3. GARDEN STATE PLAZA [1,340,000 sf], Paramus, NJ
4. YORKTOWN CENTER [1,300,000 sf], Lombard, IL
5. SUNVALLEY CENTER [1,255,000 sf], Concord & Pleasant Hill, CA