Starting at the 180° meridian and proceeding east along the equator, each 100 000-metre column is lettered alphabetically, from A through Z, with I and O omitted. Each 100 000-meter square is identified by a combination of two alphabetical letters. Our NTS sheets show the Military Grid Reference System, commonly known as the 100 000-metre square identification grid. Many National Topographic System (NTS) map sheets have been produced with the wrong two letter MGRS designators. This material updated from The Universal Transverse Mercator Grid, Department of Energy, Mines and Resources Canada, Surveys and Mapping Branch, Ottawa, © 1969, The Queen‘s Printer. Therefore the unique designation of the church if it were in the Ottawa area would be 18 T NT9293. The zone number is followed by a letter which gives the general area north or south of the equator in bands of 8 degrees. The zone, which is explained elsewhere, is one of the 60 strips of the projection. If, for some reason, a reference is required that is unique in the world, one must look in the margin of the map for the Grid Zone Designation. For most purposes this is sufficiently unambiguous. This reference is still not unique, but the same reference does not occur again for about 2,900 km (1,800 miles). Here the church would be in square NT99 and more precisely at point NT9293. Figure 3 shows a reference on a 1:250 000 map (where grid lines are usually identified by a single number). The identifying letters (two of them) are always given before the numbers. This is particularly important in the case of medium- and small-scale maps (1:250 000 and smaller), as unlettered references are ambiguous on a single map. Therefore a method has been devised to identify the 100,000-metre squares by letters which are printed in blue on the face of all NTS maps.
The Military Grid Reference System is convenient, but unfortunately reference numbers repeat themselves every 100,000 metres (100 km or about 62 miles). Wisconsin Maps – As produced by the Emergency Preparedness Committee of the Minnesota Geospatial Advisory Council.įind below links to commercial map products which include the USNG.Īs the USNG Information Center becomes aware of commercial map products which incorporate the USNG, they will be made known here.Figure 3 is an illustration of reference numbers in blue which makes the unique referencing.
#Magic maps grid reference series
Currently, only the states of Iowa and Minnesota provide a comprehensive series of USNG maps for the entire state. Learn more about the maps from the USGS US Topo Programįind below links to state systems for the distribution of mapping products which include the USNG.
#Magic maps grid reference download
Click here, or on the graphic to the left to go directly to the USGS Map Locator and Download application.These topographic maps use the USNG as the grid system. The US Topo series is provided in GeoPDF® format which can be actively used in electronic form with a GPS unit, or printed to hard copy.
Geologic Survey (USGS) provides online digital 7.5-minute digital quadrangle maps for the entire country for free. Below, find links to maps that include the USNG grid as a reference system. Since use of USNG is particularly helpful in emergency situations, reference maps that cover large areas are valuable items to have in hard copy and/or in electronic format, especially when they show the locations of political boundaries, aerial imagery and other important features, such as hospitals.
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