Peter discovers that the bomb on the DC Metro train car he found was supposed to go off somewhere along Wilson Blvd. However, he boarded the train with the bomb at the Gallery Place - Chinatown station through which the Yellow and Red lines pass. It's the Orange line which travels along Wilson Blvd.
When Peter, Rose, and Lorna are driving away from Lorna's house, she instructs Peter to "take the next exit." However, the overhead shot had already established that they were on a two-lane country road, not a highway with exits.
Peter, Rose and Lorna are walking on a Washington street when a Canada Post van drives by in the background.
A Canada Post vehicle passes by on the street.