The development of skyscrapers over 300 feet (91 m) in San Diego is attributed to the construction of the El Cortez Hotel in 1927, the tallest building in the city from 1927 to 1963. As time went on multiple buildings claimed the title of San Diego's tallest skyscraper, including the Union Bank of California Building and Symphony Towers. Currently the tallest building in San Diego is One America Plaza, standing 500 feet (150 m) tall, which was completed in 1991. The downtown skyline contains no super-talls, as a regulation put in place by the Federal Aviation Administration in the 1970s set a 500 feet (152 m) limit on the height of buildings due to the proximity of San Diego International Airport. An iconic description of the skyline includes its skyscrapers being compared to the tools of a toolbox.