June 9 Washington Mall "World's Largest Gathering" of Girl Scouts (near Wash. Monument)

from WASHINGTONPOST dot-com (local AP coverage of event, 6 p.m. Eastern, June 9, 2012):

Girl Scouts from across the country gathered on the National Mall to celebrate the organization’s 100th anniversary with celebrities including Mandy Moore.

Organizers say they expected 200,000 participants Saturday for the largest gathering of Girl Scouts in history. They were hoping to set a Guinness World Record. Girls from every state are expected to attend.

The crowd was also contending with high temperatures. Authorities say dozens were treated for heat-related illnesses, and at least 15 people were transported to hospitals.