Stuff to do in Washington DC...

National Geographic Museum Store

https://www.nationalgeographic.org/society/events-and-experiences/

DEA Museum

 https://museum.dea.gov

National Law Enforcement Museum

www.lawenforcementmuseum.org

National Postal Museum

www.postalmuseum.si.edu

National Inventors Hall of Fame and Museum

www.invent.org/honor/hall-of-fame-museum

Union Station

https://freetoursbyfoot.com/union-station-washington-dc/

Zero Milestone

https://www.lonelyplanet.com

Dupont Underground

(if the art’s not too scary): www.dupontunderground.org

National Archives

www.archives.gov/museum

Library of Congress

www.loc.gov

National Museum of Natural History

www.naturalhistory.si.edu

Bit further afield...

Air and Space Museum

https://airandspace.si.edu/visit/udvar-hazy-center

Baltimore and Ohio Railroad Museum

https://www.borail.org

Harper’s Ferry

https://www.lonelyplanet.com/usa/west-virginia/harpers-ferry

National Capital Trolley Museum

https://www.dctrolley.org/