Washington DC: National Mall Events

AI 追蹤條件：Public events on and around the National Mall in Washington, DC: the National Cherry Blossom Festival and peak bloom dates, July 4th celebrations and fireworks, Smithsonian Folklife Festival, memorial ceremonies, and major public gatherings. Only include confirmed dates from official organizers or reliable news; always verify the source's year — never reuse a past year's peak bloom dates.