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 National Historic Site in 1837. The city blocks where the National Gallery of Art now stands became a fashionable residential area in the 1830s. In the 1860s, the area saw significant deterioration despite continuing improvements to Pennsylvania Avenue itself. Pennsylvania Avenue was lit with coal gas streetlights in 1851. The avenue was one of the few fully lit streets in the entire city of Washington. In July 1862, a horse-drawn trolley line was built along the street between the Capitol and White House. But despite these many improvements, much of the Pennsylvania Avenue Historic Site south of Pennsylvania Avenue had become a disreputable