The tallest building in Los Angeles, California is the Wilshire Grand Center, which is tall and became the city's tallest building in 2017. It is also the tallest building in the state, the tallest building in the U.S. west of the Mississippi River, as well as the 15th-tallest building in the U.S. overall. Seven of the ten tallest buildings in California are located in Los Angeles. The 73-story U.S. Bank Tower, which rises in Downtown Los Angeles and was completed in 1989, is now the second-tallest building in Los Angeles. The history of skyscrapers in Los Angeles began with the 1903 completion of the Braly Building, which is often regarded as the first high-rise in the city; it rises 13 floors and in height. The building, originally constructed as a commercial structure, has since been renovated into a residential tower and is now known as the "Continental Building". In 1904, Los Angeles imposed height restrictions throughout the city, prohibiting the construction of any building taller than . An exception was made for Los Angeles City Hall, built from 1926 to 1928, which stands at . This effectively limited the height of non-government buildings to 13 stories, and was intended to address local concerns about growing congestion and over development at the time. That height limit was lifted in Downtown Los Angeles by the city government in 1957. Los Angeles (and especially downtown) then went through a large building boom that lasted from the early 1960s to the early 1990s, during which time the city saw the completion of 23 of its 30 tallest buildings, including the U.S. Bank Tower, the Aon Center, and Two California Plaza. Modern skyscrapers are difficult and expensive to construct in Los Angeles, as well as the resulting difficulty of adhering to the city's rigorous engineering standards. Nevertheless, a number of successful and iconic skyscrapers dot the Los Angeles skyline from Downtown Los Angeles (DTLA) through Koreatown, along the Wilshire Corridor and Miracle Mile, in addition to Century City and other areas of the city's west side. Other skyscraper hubs in Los Angeles include Century Boulevard by Los Angeles International Airport (LAX), the Hollywood district in central Los Angeles, as well as Warner Center, Encino and Universal City in the San Fernando Valley. Los Angeles's west side has so many skyscrapers, often Wilshire Boulevard in the Westwood District and Century City's skyscrapers are confused with being