This last episode “Consumed” saw Carol and Daryl in search of Beth. They returned to Atlanta and we saw Interstate 85, the tank that Rick hid in and other locations from season 1.
Creator Robert Kirkman talked about revisiting these locations after the episode aired. He said it helped show how far civilization has fallen, and seeing the city in that state harkens back to Day of the (1985) and other zombie films. He also said there are other important reasons why they returned to the city, but that we will have to wait until later in the city to see why.
There were some other neat little Easter eggs in this episode. Daryl smoked some Morley cigarettes (as seen in X Files and numerous other shows) and the van with the Virgin Mary statue harken to an event during Lost.
So what do you think, what other importance can the return to the city have?