The exterior for the Sewall-Belmont house, located next to the Hart Senate Office Building at 2nd Street and Constitution Avenue, NE, served as Robert Leffingwell's (Henry Fonda's) home.
The crew breaks for lunch outside of the Commerce Department Building at 14th Street and Pennsylvania Avenue, NW.
The Sheraton-Park Hotel was Senator Bob Munson's (Walter Pidgeon) home in the movie. In the 1960s, many senators roomed in hotels or apartments, and a number of them resided at the Sheraton-Park Hotel in 1961 when the movie was filmed.
“I was drawing a different scene, and Laughton ambled over and plumped down on the grass. He was looking toward the south side of the White House, and I said, I have to catch that. I got the White House in the background and the people lined up watching the filming. This is one of my all time favorites.” –Lily Spandorf