History: Architect Peter Eisenman designed the stadium using the inspiration of a barrel cactus. Pieces of the building fit together like cactus wedges, making efficient use of natural light. The result is a $450 million complex that opened in August 2006 on a 165-acre site in Glendale, less than 10 miles northwest of the Phoenix city center. The stadium is the first sports venue in North America to feature both a retractable roof and retractable playing field, allowing the natural grass to soak up the sun during the day while fans bask under the stars at night. Situated to receive the maximum amount of sunlight throughout the day, the stadium's field remains outside except during games. The natural grass tray measures 234 feet by 403 feet and is 39 inches deep. The total trip (741 feet) to roll the grass to the field takes 65 minutes.