Insets can be thought of as secondary map areas, each encased within their own
neat line. These neat lines should be of different thickness or type than other line
features on the map to adequately demarcate them from other map features. Insets
often display the primary mapped area in relation to a larger area. For example, if
the primary map shows the locales of national parks with a county, an inset
displaying the location of that county within the larger state boundary may be
included. Conversely, insets are also used to display areas related to the primary
map but that occur at some far off locale.