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
North Lawn (White House) through the northeast gate. A circular pool with fountain is centered on the north portico of the White House. Visiting heads of state enter the White House grounds, and are officially welcomed here prior to a state dinner. Public tours, which begin on East Executive Drive, exit through the North Portico, and visitors exit from the northeast gate. White House correspondents, for television news, often stand on the North Lawn with the North Portico as a backdrop. A reviewing stand is erected on the North Lawn facing Pennsylvania Avenue prior to the inauguration of the president. The president uses the