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) ("Buxus species"). The pool is planted seasonally with borders of tulips edged by grape hyacinth ("Muscari armeniacum") for spring, red geranium ("Pelargonium") and Dusty Miller ("Senecio cineraria") in summer, and chrysanthemum ("Chrysanthemum cinerariaefolium") in fall. North Lawn (White House) The North Lawn at the White House in Washington, DC, is bordered on the north by Pennsylvania Avenue with a wide view of the mansion, and is screened by dense plantings on the east from East Executive Drive and the Treasury Building, and on the west from West Executive Drive and the Old Executive Office Building. Because it is bordered by