State Topographic Map Lists

MAP-LIST HELP:

Using and Interpreting USGS Online Map Lists

General Information about USGS Topographic Maps

The U.S. Geological Survey (USGS) has been producing maps of the United States for more than a century. Among the best known of the many products of the USGS are topographic maps, which show land contours associated with hills, valleys, slopes, ridges, mountains, and other natural land features. Most USGS topographic maps also show various other kinds of information, including rivers and streams, roads and railroads, swamps and forests, and cities and towns. Many of these maps also show buildings and other manmade structures.

The actual size of USGS topographic map sheets varies depending upon geographic location and map scale. A typical map sheet from the popular topographic map series measures about 20 inches by 28 inches.

Although the USGS produces and distributes other kinds of published maps, this set of online map lists provides information only about USGS published topographic maps (and a very limited number of related maps). This online map-list site presents the same information originally published in the State Map Lists, which are distributed in paper form by the USGS Earth Science Information Centers. Please note that the data available for the State Topographic map list is current through March 2002.

Looking for Topographic Maps

This site provides three ways to look for published USGS topographic maps:

State Map Lists -- State map lists let you see maps for the particular State or territory that interests you.
Map Scale -- You can search a map list by the scale (for example: 1:24,000,1:25,000, 1:50,000).
Latitude and Longitude -- Online Map lists can be selected by 1-degree by 1-degree block of latitude and longitude.

In order to avoid lengthy downloads, the standard online State Map List normally shows only the map entries beginning with a particular letter of the alphabet. When you select a standard State Map List, the first listing you see is all of the "A" entries for the popular 7.5-minute (1:24,000 or 1:25,000 scale) maps. At the bottom of the listing you will find selection options to let you choose any map scale of interest and any starting letter. You can select a complete listing of all maps for a State, but you should be aware that such a listing may require several minutes to download.

Map Scale

The USGS publishes maps in many different scales, though the majority of USGS published topographic maps are in the 1:24,000/1:25,000-scale map series. This series is also known as the 7.5-minute map series because these maps generally each cover a single geographic quadrangle bounded by 7.5 minutes of latitude and 7.5 minutes of longitude. Sometimes maps of a particular scale (such as 1:48,000) are available for one State but not for other States. The online map lists tell you the scales for which maps are available in each State or territory.

1:24,000-scale maps are relatively detailed, generally covering an area a few miles wide by a few miles high. Maps at 1:250,000 scale are less detailed but cover the same area as 128 7.5-minute maps. A 1:2,000,000-scale map typically covers most of two or more States.

Map Type

Although almost all of the maps listed in this site are topographic maps, there are some different varieties. The listings include a description of each map's type. If you need further information about the meaning of a map type, please telephone (toll free) 1-888-ASK-USGS or telephone or visit the nearest USGS Earth Science Information Center.

Map Scale

For each map listed in this site, a latitude and longitude coordinate pair are provided. In most cases this geographic coordinate is the southeast corner of the geographic quadrangle covered by the map.

Currentness Year and Version Year

The online map lists provide two dates for most maps: the "currentness year" date and the "version year" date. Usually these dates differ by just a few years but in some cases the difference may be much greater.

The "version year" is the latest date printed under the map name on the lower right-hand corner of a map sheet. Since the number of dates and the format of dates shown on the lower right-hand corner vary from map to map, the date we have selected as the version year will differ from map to map; on some maps it will be a photoinspection date printed in red ink, on others it will be a large date printed in black or brown ink, and on still others it will be yet another kind of date. In all cases, though, it will be the most recent of the dates printed under the map name in the lower right-hand corner.

The version year is usually the same as the year when a map was printed.

The "currentness year" indicates when the information shown on the map was last collected or verified. For example, if the information shown on a map was collected through actual field surveys in 1968 but the map compiled from this information was not published until 1970, the currentness year for this map would be 1968; in this case the version year would probably be 1970. To consider another example, if a map was completed and published in 1974 and was compared with aerial photographs taken in 1995 and was found to be still accurate, the currentness year would be 1995 even though the version year would still be 1974.

In these online map lists, a footnote is used to identify currentness-year dates reflecting photo inspections of maps. These photo-inspected maps have not been modified and the printed editions (though marked with earlier version years in many cases) are still current.

How to Purchase USGS Maps

To purchase USGS maps, please see our ordering instructions.

| State Topographic Map List Home | Eastern Region Geography | Geography |

U.S. Department of the Interior — U.S. Geological Survey — 509 National Center, Reston, VA 20192, USA
URL: http:// erg.usgs.gov /maplists/howtoselectmaps.html — Page Maintainer: USGS Eastern Region PSC 4
Page Contact Information: Web Administrator
Last modified: 06:52:23 Fri 19 Oct 2007 — USGS Privacy Policy and Disclaimers — Accessibility