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Maps: Perkins Collection

The Map Collection at Perkins Library and sources for online maps and related information.

Finding a paper map

Location of collection


  • Many maps are in the library catalog.  You can use the Advanced Search and limit the format to Map, or after a search you can limit Format to "Map" under "Refine Your Search" in the left column.
  • Many maps in large sets (e.g., USGS topographic maps or NGA Nautical Charts) are not in the library catalog.
  • In the standard keyword search use the terms "maps" or "atlas" with geographic terms (e.g. <France history atlas> or <guam maps>). This will find flat maps in the Map Collection, atlases anywhere in the library, and books that have maps in them (when noted in the catalog record). For atlases, also try a title keyword search in the basic search for the word atlas and the name of the country.
  • If you understand the call number construction you can also find things just by browsing (see below).

Browsing the collection

Call number parts include:

  1. "class" (geographic area: begins with "G" and then a 4-digit numeral)
    Clickable index map to find country call number stem / States of the US call number stems (scroll to G 3690)
    • Ends in 0 : general purpose maps, often topographic maps
    • Ends in 1 : subject map; will include a subject code in call number
    • Ends in 2 : physical region within larger geographic area
    • Ends in 3 : administrative area within a larger administrative area
    • Ends in 4 : city
  2. sometimes an alphanumeric subject code, or a code for a sub-area or a city (see box to right)
  3. date (usually the date being depicted, except for "historical" maps with an .S subject code, in which case the date is the publication date)
  4. a code for "author" (usually the publisher) or title
  5. sometimes a reprint date if the map is a facsimile

Types of Maps

Topographic Maps

  • Usually come in sets, with the class portion of the call number typically ending in the numeral "0"
  • Symbols may denote quarries, forests, archaeological sites, "ruins," etc.
  • Show human culture (towns, some structures, modern roadways)
  • Show rivers and streams
  • Contour lines indicate elevation (labeled with number) and slope (spacing of lines: closer together is steeper)

Subject Maps

  • The main class portion of the call number (1st line) typically ends in the numeral "1"
  • An alphanumeric code, usually on the 2nd line of the call number, indicates the primary subject of the map
  • Examples:
Subject: Alphanumeric code begins:
Mines and Mineral Resources

Geologic Maps

  • Subject code .C5
  • Bedrock geology shows solid bedrock often under the surface; "Surficial" or "Quaternary" geology represents recent sediments on top of the bedrock.
  • A simple and fairly generic legend.
  • Detailed standards for symbols on geologic maps.


If there's nothing for the area you're studying, then look for sets of maps covering any larger area that encompasses it.  For instance, for detailed areas in Mali, look for sets covering West Africa or Africa or the world, not just for a single country.