<P> The Arch also became one of several U.S. monuments placed under restricted airspace during 2002 Fourth of July celebrations . In 2003, 10 - foot - long (3.0 m), 32 - inch - high (81 cm), 4,100 - pound (1,900 kg) movable Jersey barriers were installed to impede terrorist attacks on the arch . Later that year, it was announced that these walls were to be replaced by concrete posts encased in metal to be more harmonious with the steel color of the arch . The movable bollards can be manipulated from the park's dispatch center, which has also been upgraded . </P> <P> In 2006, arch officials hired a "physical security specialist," replacing a law enforcement officer . The responsibilities of the specialist include risk assessment, testing the park's security system, increasing security awareness of other employees, and working with other government agencies to improve the arch's security procedures . </P> <P> Built as a monument to the westward expansion of the United States, the arch typifies "the pioneer spirit of the men and women who won the West, and those of a latter day to strive on other frontiers ." The arch has become the iconic image of St. Louis, appearing in many parts of city culture . In 1968, three years after the monument's opening, the St. Louis phone directory contained 65 corporations with "Gateway" in their title and 17 with "Arch". Arches also appeared over gas stations and drive - in restaurants . In the 1970s, a local sports team adopted the name "Fighting Arches"; St. Louis Community College would later (when consolidating all athletic programs under a single banner) name its sports teams "Archers". Robert S. Chandler, an NPS superintendent, said, "Most (visitors) are awed by the size and scale of the Arch, but they don't understand what it's all about...Too many people see it as just a symbol of the city of St. Louis ." </P> <P> The arch has also appeared as a symbol of the State of Missouri . On November 22, 2002, at the Missouri State Capitol, Lori Hauser Holden, wife of then Governor Bob Holden uncovered the winning design for a Missouri coin design competition as part of the Fifty States Commemorative Coin Program . Designed by watercolorist Paul Jackson, the coin portrays "three members of the Lewis and Clark expedition paddling a boat on the Missouri River upon returning to St. Louis" with the arch as the backdrop . Holden said that the arch was "a symbol for the entire state...Four million visitors each year see the Arch . (The coin) will help make it even more loved worldwide ." A special license plate designed by Arnold Worldwide featured the arch, labeled with "Gateway to the West ." Profits earned from selling the plates would fund the museum and other educational components of the arch . </P>

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