The Map Library uses the Library of Congress call number system for most paper maps. Each geography is assigned a call number range, with subjects within each geographic area under it.
Use the tabs to find maps by:
U.S. State or
Use the boxes to the right to find out how to read the call numbers.
Most maps are arranged by call number under G.
Cities and Counties are designated in the call numbers for US States in the following way:
G4080 maps of the entire state of Ohio or another state, G3810 (New Jersey), G3820 (Pennsylvania), G3890 (West Virginia), etc.
G4081, subjects in the states
G4082, regions and natural features of the states
G4083 .P7, Portage County Ohio or other counties, G4083 .A2 (Adams County), G4083 .B4 (Belmont County), etc.
G4084.K3, Kent, Ohio or other cities and towns, G4084 .A3 (Akron), G4084 .C5 (Cleveland), etc.
How Subjects appear:
.C3 Hydrogeology/ hydrology
.C4 Ground water
.F7 Political boundaries
.G3 Natural Resources
.P2 Roads/ transportation
G4083 .P7 (Portage county) C5 (Geology)
G4084 .A3 (city of Akron) .P2 (Roads)