Ain't nothing happening in DC that day except Trump's stupid military parade.
From CBS News:
On June 14, cities across the United States are planning to host "No Kings Day" events as part of a coordinated protest against the Trump administration.
*snip*
Organizers behind the national "No Kings" movement are calling [Trump's military] parade a "made-for-TV display of dominance" orchestrated for Trump's birthday, and are encouraging protesters to instead rally in communities outside the nation's capital.
To that end, there is no "No Kings" event in Washington, D.C. Philadelphia's "No Kings" protest is being promoted by organizers as Saturday's "major flagship march and rally."
Saturday's "No Kings" march and rally in Center City is slated to begin at 12:30 p.m. in LOVE Park. According to the City of Philadelphia, people are expected to start gathering in the area as early as 10 a.m.
Protesters are set to then march from LOVE Park down the Benjamin Franklin Parkway toward Eakins Oval and the Philadelphia Museum of Art, where a rally is scheduled from 1-3 p.m.
Full article here:
https://www.cbsnews.com/philadelphia/news/no-kings-protest-philadelphia-sunday-june-14/
Based on the above, it sounds like your best bet is either go to Philly or do the local one in H-burg.