Pennsylvania Avenue lighthearted celebrations, including a series of day- and nighttime Shriner's parades in the 1920s and 1930s. Thomas and Concepcion Picciotto are the founders of the White House Peace Vigil, the longest running anti-nuclear peace vigil in the US, at Lafayette Square on the 1600 block of Pennsylvania Avenue. After the Oklahoma City bombing in 1995, the Secret Service closed the portion of Pennsylvania Avenue in front of the White House to all vehicular traffic. Pedestrian and bicycle traffic, however, was still permitted on the sidewalk. After 9/11 this policy was made permanent. Near the White House traffic is redirected to
Pennsylvania Avenue on October 27, 1972 to rehabilitate the street between the Capitol and the White House, an area seen as blighted. The new organization was given the mandate of developing Pennsylvania Avenue "in a manner suitable to its ceremonial, physical, and historic relationship to the legislative and executive branches of the Federal Government". In 2010, the District of Columbia designated Pennsylvania Avenue from the southwestern terminus of John Philip Sousa Bridge to the Maryland state line to be a "D.C. Great Street". The city spent $430 million to beautify the street and improve the roadway. Ever since an impromptu procession formed