(1) A map located within the border of a larger map depicting an area of the main map at a larger scale. (2) A small scale key map (located in the surround) showing the area of the main map in the context of a greater region. (3) A map showing a region outside the main map that is significant to the theme of the principal map. (See Surround).
Enlargement of a overly detailed portion of a map -- will appear on the same map sheet or a separate map sheet.
a small map, inset into the frame of the larger, used to help readers see where the detailed area is located