The World Trade Center was already world famous before September 11, 2001, but after that day it will be remembered for generations for what its destruction symbolized and the events that occurred as a result. The Twin Towers were completed in 1973 and 1972 respectively, and the other four WTC buildings were completed by 1974. They made a striking addition to the Manhattan skyline and very quickly became icons, not only of success, power, and strength, but also to some, of greed. They contained 10 million square feet of office space, much of which was not filled, and soon before the attacks, Port Authority had begun to loan some offices to artists for free studio use. Today, there are many plans for new structures, and 1 World Trade Center was completed last week, and is the tallest building in the Western Hemisphere.