Unlike many consumer solutions that offer predefined and already extracted regions, StreetMap allows users to define an area that exactly corresponds to their needs. The polygon selection tool allows simple areas, as well as complex areas, to be selected for extraction. Here are a few guidelines to follow when defining the selection area:
Keep the selection compact. Long, narrow stretches of data frequently force routing on a street level while ignoring a convenient highway nearby. In addition, traversing street segments increases route search time.
Limit the selection to the actual area of travel. Unless frequent travel to places outside the work area are common, don't include them in the selection. Another dataset for an out-of-town trip can always be extracted at a later time.