The Transamerica Pyramid is a pyramid-shaped 48-story modernist skyscraper in San Francisco, California, United States, and the second tallest building in the San Francisco skyline. Located at 600 Montgomery Street between Clay and Washington Streets in the city's Financial District, it was the tallest building in San Francisco from its completion in 1972 until 2017 when the newly constructed Salesforce Tower surpassed its height.

From Wikipedia