'The use of elevation contour lines to show the shape of the Earth's surface. Contours make it possible to show the height and shape of mountains, the depths of the ocean bottom, and the steepness of slopes.'
from https://www.usgs.gov/faqs/what-a-topographic-map?qt-news_science_products=0#qt-news_science_products
Call numbers contain measurements, each distinctive to the map.
'The scale used for all modern USGS topographic maps is 1:24,000. That covers a quadrangle that measures 7.5 minutes of longitude and latitude on all sides, so these are also referred to as 7.5-minute maps, quadrangle maps, or "quad" maps.'
from https://www.usgs.gov/faqs/what-a-topographic-map?qt-news_science_products=0#qt-news_science_products
At the SD State Library, South Dakota topo maps are located in the Federal Government Map Case, from Alcester to Zeona, an extinct town once located in Perkins County.
Many South Dakota cities and towns are listed in our catalog, available in paper format, including:
I 19.81:N4307.5-W9630/7.5
Alcester quadrangle, South Dakota : 7.5 minute series (topographic) / mapped, edited, and published by the Geological Survey, 1968
I 19.81:N4415-W9815/7.5
Wolsey SE quadrangle, South Dakota--Beadle Co. : 7.5 minute series (topographic) / mapped, edited, and published by the Geological Survey, 1973
I 19.81:N4507.5-W10245/7.5 / 31583007834870
1:25 000-scale metric topographic map of Zeona, South Dakota, 1980 / produced by the United States Geological Survey in cooperation with State of South Dakota agencies.
Various online topo maps can be found at: https://www.usgs.gov/core-science-systems/national-geospatial-program/us-topo-maps-america
The SD State Library is a federal depository library and provides access to print and electronic federal government publications. Print publications are available via interlibrary loan. Electronic publications are linked from the state library online catalog.