The dress Lucy is wearing when she and Harry attempt to go out without Eddie and Viv was one she previously wore on "I Love Lucy" and became famous in the "glamor Lucy" photo that was eventually featured on her U.S. postage stamp.
Although the town of Danfield, where Lucy and Viv live, is fictional, the towns they travel to by car and train -New Rochelle, NY and Ridgefield, CT -are real.