Put your city on the map in 4 layers. Create an artistic old map of your area. Here’s what you should be achieving:
Step 1: Getting the actual map
Go to maps.yahoo.com, find your area and zoom in to a desired level—I went in somewhere between City and Street view in some area in Bucharest, Romania but you can also do a Country view. If your part of the world isn’t covered by yahoo maps, try google mapsor get a regular image of a map from the area you need.
Hit the PrintScreen key, go in Photoshop and paste it in a new document and then Crop (C key) the image keeping only the desired part. Use the Patch Tool or the Healing Brush Tool to remove the center cross.