The TransAmerica Tower in San Francisco designed by architect William Pereira is among the seven wonders of the precast world because it showcases the heights that precast can attain, and because it exemplifies how Pereira used precast to create his unmistakeable style. Pereira often used precast concrete to create geometric facades.

Built in 1972, the tower is currently considered the 105th tallest building in the world and the tallest precast structure. The precast panels use a beautiful crushed quartz stone and are attached to a steel frame. Every ten years, the building goes through a thorough cleaning process to keep it white stone shining.

Another factor that makes this an wonder in the world of precast concrete is that it sits in a seismically active region and had to be engineered to withstand earthquakes. During the 1989 7.1-magnitude Loma Prieta earthquake, the 48 story structure shook for more than a minute, swaying almost a foot from side to side, but remained undamaged. Clearance between the panels allows lateral movement, and a unique truss system above the fisrt floor supports both vertical and hoirzontal loading.