No Way Out

Lt. Comm. Farrell (Kevin Costner's character) is being chased by some military intelligence types after he leaves the Pentagon. He gets away by jumping over the rail of I-395 (not sure if it was on the Virginia or DC side of the Potomac River), runs a few blocks, through a door of a building, down some stairs to a subway train, and emerges into a mall where he finds a friend of Susan's (Sean Young's character). Problems:

Farrell would have had to run over a mile to the place where he got the subway - that door is part of a mini-mall in the Georgetown neighborhood - AND he would have had to cross the Mall.

Second, Farrell was in Washington, but the subway train he got on was clearly marked on its end with the logo of the Baltimore MTA. (Sure, this one is only a quasi-nit, because back in the 80s, DC forbid filming in their Metro system.)

Third (and I can't completely verify this one), Farrell finds Susan's friend at White Flint Mall, which (if my DC source is correct) was not an operating stop on the Red Line when the movie was made. OK, sure, he could have gotten off at Grosvenor and taken the bus, but still...

Sure, this one is only a quasi-nit, because back in the 80s, DC forbid filming in their Metro system.
A nit is a nit, even if there is a real life explanation. Hence the quote, "I'm a nitpicker, I don't deal in reality." ;-)
Also the filmmakers could have either covered the Baltimore logo with a copy of the DC logo, or they could have filmed the scene on a Hollywood set made up to look like the DC Metro. There were ways the filmmakers could have made it work.

Not a bit, but an observation - Farrell slips into a phone booth to make a call. Phone booths were everywhere when the movie was shot in 1986. Try to find a free-standing pay phone, much less a phone booth, these days.