Gare Du Nord to Invalides

Not sure how the character who goes to Paris is able to walk out the front door of Gare du Nord in 1849 and a) see the Esplanade des Invalides, which is 6km away and b) see it as it looked for the World's Fair in 1889...

Yeh, it is just a movie but it really pisses me off how they always just make up the geography of Paris as they go along.