Topographic Map Scale

Two kinds of stand-level maps include: Transportation maps and Topographic maps. The WIU Libraries have topographic maps for every U. Thivierge and. The map shows where the hills and valleys are and how steep they are. pdf), Text File (. A map is a two-dimensional representation of the three-dimensional world you'll be hiking in. Connecticut USGS Topographic Map Quadrangles Danbury - Hartford South. Vertical Scale (contour interval): All maps have a horizontal scale. Maps published at this scale cover 7. • Contain less detail. o Map series. 5 minute) series maps are the most detailed topographic maps available for Kansas. Low price for YUGOSLAVIA (Serbia) - SREMSKI KARLOVCI Topographic MAP 1956 - Scale 1 : 50000 check price to day. COUNTY GENERAL HIGHWAY MAPS These maps were produced by the Kentucky Department of Highways. These maps show many features in addition to the brown elevation lines that show topography. Durable, waterproof plastic map; Folded. Be sure to indicate the units you are using. There are 35 topographic maps at the 1:100,000 scale or (30 x 60-minute maps) that cover Arkansas. Connecticut USGS Topographic Map Quadrangles Jewett City - Norwich. These maps can be used as hardcopy presentation backdrops or for locating geographic features. 5-minute quadrangle maps. The 7-foot-wide, 4-foot. Architects and urban planners use Cadmapper to save hours of routine drawing. Full color maps; Contour lines represent the elevation and shape of the land. 17 Mb) The original format of the digital data is DGN Conversion to SHP and DWG formats is possible Topographic chart, Scale 1:2 000, for the central part of Riga City is available as WMS service. Includes complete geographical coverage of New England from the 1890s to 1950s. example, "This map is an enlargement of a 1:20,000-scale map drawing," or "This map is an enlargement of a 1:24,000-scale published map. Queensland -- Maps. The Topo50 map series provides topographic mapping for the New Zealand mainland, the Chatham Islands, and offshore islands at 1:50,000 scale. Historical topographic maps help consultants and engineers determine how topography has changed over time with a property’s development, and may indicate possible environmental risks. , 30', 15', etc. The map scale defines the ratio between the measure of a feature represented on the map relative to the measure of that feature on the earth’s surface; at the 7. 1 inch on the map equals 24000 inches in the real world, which is the same as 2,000 feet. All of its maps show features in metric, for example elevation is in meters. Introduction Topography means "the shape of the land" and thus topographic maps illustrate the scale, width, length, and height of land surface features. On Red Hill (841500 810750 Kra-35) the tuffs are welded, but lack the large scale eutaxitic fabric. Three forms of scale Verbal Scale. For each map com-ponent, references are provided to exercises in other Tutorial booklets that provide provide step-by-step instructions for the relevant operations. The WIU Libraries have topographic maps for every U. The map details are enhanced by use of colors and symbols. This page presents a 1:24,000 scale USGS topographic quadrangle map showing the entire project area and surrounding landscape to approximately ½ mile. The scale on the topo map is found at the bottom center of the map. In the construction of highways, pipelines, railroads and canals, good. Slope and Topographic Maps Have you ever traveled a long way out in the countryside either hunting, mountain biking, or just for a hike? How did you find your way around? Chances are you used a topographic map. Enjoy the video featuring JC and Mathaus Mortier. topographic map. The data are extracted from aerial photography at a scale of 1:40,000 taken at an altitude of 6,300 meters. View and download free USGS topographic maps of El Paso, Texas. Medium-scale topographic maps are made or updated primarily by means of aerial photography. -Show natural and man-made features-Standard scale is 1:24,000 (also known as 7. Only Adirondack and some Finger Lakes region maps are available at this time. Look for the height and shape of the ground which is shown on 1:25 000 scale maps by brown contour lines. The source digital vector data used to produce the Provincial Access/Topographic Map Series is also available under the Open Government Licence - Alberta and is distributed by AltaLIS Ltd. Download the free, full-sheet 7. Topographic Maps are representations of the real world, complete with hills and valleys, on a flat surface. They accurately depict the location of natural and man-made features by means of symbols and colour, and elevation by means of spot-heights and contours (20m interval). An elevation profile or a topographic profile is a two-dimensional cross sectional view of the landscape. This also clears the associated products from the Products Pane. Topographic Maps Lab. 5 minutes quadrangle map because it covers a four-sided area on the Earth’s surface. Topographic maps use contour lines, lines of equal elevation, to represent the vertical dimension (height) of the landscape. 5 The scale of the topographic is … A Five times larger than the orthophoto map B Five times smaller than the orthophoto map. Map features may be represented as points, lines, or polygons. If you walk along a contour. Bushwalkers and map sellers say the decision by Geoscience Australia to stop printing and selling topographic maps will put people's safety at risk and impact on our understanding of remote Australia. This collection is now a legacy product that is no longer maintained since May15, 2013. Its high level of detail makes this scale topo map ideal for recreational activities, such as hiking, walking and bicycling. What is a map? A map shows a scaled representation of any real-world location or object on a two-dimensional surface. The Key is essential since it contains what each symbol on the map stands for. Map Scale Is this to scale? Large Scale and Small Scale Maps Scale determines the amount of detail a map will show. The popular USGS topographic quadrangle maps (often called 'topos' or 'quads') are available for the entire state. Physical Features of Michigan. Accessing USGS topographic maps has never been easier. Maps and Data Toggle Dropdown Arkansas State Maps Fossil Fuel Maps Geohazard Maps Geologic Maps Mining Web Map Topographic Maps Structure Maps Water Maps Well Logs, Cuttings and Cores Publications Toggle Dropdown. Geological Survey (USGS) publishes maps at various scales. SHOP ONLINE FOR NATMAP 1:50,000 TOPOGRAPHIC MAPS BY CLICKING THE LINKS BELOW - NATMAP 50K scale A - C - NATMAP 50K scale D - F - NATMAP 50K scale G - I - NATMAP 50K scale J - L - NATMAP 50K scale M - O - NATMAP 50K scale P - R - NATMAP 50K scale S - U. Each map has a map scale that expresses the relationship between distance on the map and actual distance on Earth’s surface. Includes prospect pits, mine shafts and adits, quarries, open-pit mines, tailings piles and ponds, gravel and borrow pits, and other features. Maps and Geographic Information Systems: Topographic. Custom-printed topographic (topo) maps, aerial photos, and satellite images for the United States and Canada. A topographic map provides the frame of reference upon which most geologic maps are constructed. For highly detailed mapping of more densely. (Topographic map in scale 1:25000) phase was commended to the private geodetic companies in public and open tenders. They are useful for a wide range of activities such as local navigation by vehicle or on foot, locality area planning and study of the environment. If you are searching for a 1:25 000 map series, use the state as a search term. The fractional scale commonly requires unit conversion. 5-minute quadrangle" maps. * Up to Topographic Topic List *. 1:12 500 detailed colour topographic map (8cm = 1km) depicts all trails, tracks and roads, features of interest, park facilities, emergency location markers, bus stops elevation is represented via a hillshade and contours includes details about all the bushwalking and cycling trails, features of. Map scales are typically expressed as unitless fractions. This lesson will help students learn how to read that map. medium to large scale map that shows a precise map of the terrain. o Map sheet name(s). How to plot a small-scale topographic map with matplotlib? Default image size is 5400x2700, which makes it slow to plot and vague in small-scale maps. The scale used for most U. Geoscience Australia has complete 'small scale' reference map coverage of Australia at scales of 1:2. By definition, the topographic detail on a small-scale map is compressed, making it difficult to associate features on the map with features in the field, particularly subtle ones. 5-minute series (created from 1947-1992). Consult a licensed land surveyor for actual boundary location and acreage. Full color maps Contour lines represent the elevation and shape of the land. FSTopo maps are 7. Map Scale: Maps come in a variety of scales, covering areas ranging from the entire earth to a city block (or less). TOPOGRAPHIC MAPS. The US Topo maps are constructed in GeoPDF® format from key layers of geographic data - orthoimagery, roads, geographic names, contours and hydrographic features - found in The National Map, which is a nationwide collection of integrated data from local, State, Federal, and other sources. The collars may be useful for identifying reprints and other details. Define small-scale map. , most topographic maps are made by the U. Without symbols, we wouldn't have maps. Lake Ray Hubbard topographic Map. This collection includes 154 topographic quadrangle maps with scales ranging from 1:125,000 to 1:24,000. I can unsubscribe any time using the unsubscribe link at the end of all emails. This is the preferred map for armored, mechanized, and mounted operations in deserts or flat terrain. If you didn't know that you never put a compass rose in water, it’s time to let Tim and Moby give you the latitude and longitude of map reading. Each map is approximately 20 inches by 27 inches. Add to Compare. Any scale can be used for a map, but a few common scales have been settled on for use by most organizations: 1:24,000 - primary scaled used by USGS for mapping the United States in topographic form. The map shows where the hills and valleys are and how steep they are. This map series is now available from Alberta Environment and Parks as a fee free download in Adobe PDF format under the Open Government Licence – Alberta. US Topo Series added to topoView We've added the US Topo series to topoView, giving users access to over 3 million downloadable files from 2009 to the present day. This collection includes 154 topographic quadrangle maps with scales ranging from 1:125,000 to 1:24,000. How to Read Topographic Maps. There are three ways to get full-scale plots of USGS quadrangle maps, both US Topo and Historical Topographic Map Collection. 01 meter coordinate precision). A small circle may mean a point of interest, with a brown circle meaning recreation, red circle meaning services, and green circle meaning rest. This type of scale is known as a ratio scale and what it means is that one inch on the map is equal to 24,000 inches (or 2000 ft) in the real. 5 minutes of longitude and 7. 4 State the scale of the Orthophoto map as a word scale 3. Contour Map Generation •In the field, points and their elevations are measured using automatic levels, total stations, or GPS devices •Geotechnical engineers use these points to generate topographic maps. 5 minutes of longitude and are commonly called 7. The files have not been updated since that time, and many of the maps are more than 30 years old. a topographic map. They are drawn to scale, meaning that any two points have the same relative position on the map as they do on the ground. Your map can tell you a lot -- details about an area's elevation, the best way to ascend a peak or how to. The ratio scale on this map is 1:24,000. Students need both practice and imag-ination to learn to visualize hills and. The scale of the map is determined by the amount of real-world area covered by the map. To represent the three. 5 minutes of longitude; they are commonly called "7. In addition to the standard image overlays of Map, Satellite and Hybrid for Google Maps, the Active Trails website has an additional overlay button - Topo, for topographic maps. For questions or comments concerning this dataset please contact [email protected] Site centered maps can be made at scales between 1:12,000 and 1:55,000. I should note here that I then changed the scale to 1:50,000 because it gives you the most area on the printed map. This application uses licensed Geocortex Essentials technology for the Esri ® ArcGIS platform. Ground area, rivers, lakes, roads, distances between features, and so on must be shown proportionately smaller than they really are. Here’s another in a series (see here and here) of interesting maps that address scale. The choice of small-scale maps always comes down to the intended use of the final map. 5 minutes of latitude and 7. View all of our high-quality shaded relief USGS topo maps, Forest Service maps, satellite images, and custom map layers for free. These are the maps that you as a soldier or junior leader are most likely to encounter. Connecticut USGS Topographic Map Quadrangles Jewett City - Norwich. USGS TOPOGRAPHIC MAPS FOR GOOGLE EARTH Over 50,000 1:24k scale topographic maps -- once in Google Earth, click on the green "buttons" to get to the second grid with blue buttons that let you view a particular map; UNITED STATES TOPOGRAPHIC MAPS ONLINE. The contour lines indicate a change in elevation by the scale amount. There is a standard ratio format for map scales e. To see which map(s) cover which unit(s) take a look at the grid. USGS topographic maps have both bar scales and RFs. Click to Explore via interactive map. Historical Topographic Maps 7. o Map sheet name(s). This video describes topographic mapping basics such as determining the scale and location (UTM and State Plane coordinate systems) How to Find Your Position on a Topo Map Using a GPS & UTM. Without symbols, we wouldn't have maps. Medium Scale Maps Medium scale maps • Cover a larger area. PLEASE NOTE: These maps are the latest USGS standard topographic maps. • Land use map. The size of the map is derived by selecting a map scale that is neither large nor small. This is added to the IMW zone number and another unique number is created. These are the maps that you as a soldier or junior leader are most likely to encounter. Map scale is often confused or interpreted incorrectly, perhaps because the smaller the map scale, the larger the reference number and vice versa. A person who can read a topo map can find out the location of peaks, valleys, ridges and saddles, among other land features. List of Counties. 3 Which scale is bigger? Give a reason for your answer. Demonstrate use of the scale on your state map. Old maps of Birmingham on Old Maps Online. Physical Map Sample. A topographic map may or may not include shaded relief to help visualize steep slopes. JOHNSON FOREST, Greenbrier County, WV (topographic map) Elevation Range: 2017' - 3244' +/-; Google Coordinates: LAT 37. ArcGIS Online USA Topographic Maps; New Zealand Topographic Basemap (LINZ) When planning a trackless hiking expedition in a remote region where detailed maps are hard to find or nonexistent, the following maps in ArcGIS Explorer might also be of value beside the Soviet military maps in Topomapper or any other topographic map. Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. Topographic Map Indexes. Small Scale Vs. Numbering Other Scale Topographic Maps. Map Scales, Symbols, and Colors In order to be useful, topographic maps must show sufficient information on a map size that is convenient to use. This is a special ruler that is drawn below a map that can be used to measure an area or distance. Soviet military topographic map sets. The map is a representation of terrain detail. The basemap was compiled to uniform cartography using a variety of best available sources from these data providers. "NTS" means National Topographic System map sheets produced by the Surveys, edition 2 of the Norman Wells NTS map sheet number 96 E, produced at a scale of 1:250,000;. This is a searchable directory to the entire collection of United States Geological Survey (USGS) Topographic Maps including the 1:250,000 scale maps to the more detailed 1:24,000 scale maps. They are useful for a wide range of activities such as local navigation by vehicle or on foot, locality area planning and study of the environment. • Land use map. Answers are provided for all ten of the topographic map exercises. Download the free, full-sheet 7. Most map symbols are conventional signs as they are understood by everyone around the world; for example a lighthouse and church. You precisely center your map anywhere in the US, choose your print scale for zoomed-in treetop views, or panoramic views of entire cities. The most detailed national map coverage is the 1:24,000-scale topographic quadrangle series. You base these plans and maps on. The 1:10 000 orthophoto maps combine all the advantages of conventional line maps and aerial photography. Geological Survey publishes maps at various scales. To represent the three. Called contour lines, they can tell you whether you’ll be hiking uphill, downhill, or over flat land. 5 minutes of both latitude and longitude). Demonstrate use of the scale on your state map. World Elevation Map for Elevation and Elevation Maps of Cities/Towns/Village. This is more than adequate for cadastral surveys. 0 SP1, control points were placed using a map scale of approximately 1:75,000 with the data frame spatial reference set to GCS North American 1927. ) To scroll the zoomed-in map, swipe it or drag it in any direction. In 1879, the USGS began to map the Nation's topography. These are images of U. Selecting the appropriate scale depends on the size of the sheet of paper and the accurate placement of features. Step 1: Select Area of Interset Draw polygon to select lidar products for area of interest. " Major water bodies are used for map names when appropriate because they show the greatest contrast and are easily recognized. USGS topographic maps have both bar scales and RFs. The first means of measuring distance on a topographical map, or any map, is the straight line distance, which indicates a straight distance "as the crow flies. Any scale can be used for a map, but a few common scales have been settled on for use by most organizations: 1:24,000 - primary scaled used by USGS for mapping the United States in topographic form. For example, a 1:100000 scale map is considered a larger scale than a 1:250000 scale map. Scale allows you to convert map distance into real-life distance. This is added to the IMW zone number and another unique number is created. The US Topo series is a latest generation of topographic maps modeled on the USGS historical 7. Readings: Online: GEOG 481 Lesson 6. The USGS was entrusted with the responsibility for mapping the country in 1879 and has been the primary civilian mapping agency of the United States ever since. Gosford, 9131-2S, 1:25,000 scale (4cm=1km) topographic map covering Brisbane Water, Gosford, Somersby, Woy Woy and Terrigal on NSW Central Coast. Contour Lines, spot elevations, coastlines and bodies of water from the raster image are extracted, converted to digital vectors and given elevation values. You precisely center your map anywhere in the US, choose your print scale for zoomed-in treetop views, or panoramic views of entire cities. A 1:250 000 scale topographic map. Define small-scale map. The Topo50 map series provides topographic mapping for the New Zealand mainland and Chatham Islands at 1:50,000 scale. This system hinged on two features: a well defined, regular, smaller scale grid was developed for the whole Earth's surface. - Write down the reading after measuring the line, e. Raised Relief Map Of Glacier National Park Montana, Woman S Body Recovered From Lake Ray Hubbard, Nctcog Considers Plans for New Bridge Over Lake Ray Hubbard, the Howdygram the Grass is soaked Trees are Smiling and, Bones Found In Submerged Car at Lake Ray Hubbard Nbc 5, Rowlett Say Yes to Dallas. The legend may also include a map scale for help in determining distances. Click on a quadrangle on the map below to download the digital map. At a scale of 1:50,000, Topo50 maps show geographic features in detail. The length of the plots is scaled such that the physical length scale is the. Verbal Scale: 1 inch = 2000 feet. Topographic maps are typically used by the military, architects, mining companies and even hikers. Geological Survey discontinued this series several years ago and many of the maps may no longer be available. maps that use contour lines to show elevation. For example: “Australia AND topographic AND 1000000” with format ‘Map’ yields these results. they will tell you whether an area is steep or level. Map Scale (bottom center of map) The map scale indicates the ratio or proportion of the horizontal distance on the map to the corresponding horizontal distance on the ground (Figure 2-5). An elevation profile or a topographic profile is a two-dimensional cross sectional view of the landscape. f ¢ ¥ f ¢ IA d n e d G l e n Roc k R e s e r v o i r Upper Bridge Lower Bridge Station 1 !Ö Station 2 !Ö Station 3 !Ö Station 12 !Ö Station 10 !Ö Station 11 !Ö. Topo50 maps. Learn how bar scale, fractional scale and verbal scale are used to find real world distances from measurements on map. A topographic map is a two-dimensional map that represents a three-dimensional area using contour lines to indicate elevation of the earth's surface. The 1:50 000 topographical maps are the largest maps providing full coverage of South Africa. Find the elevation and coordinates of any location on the Topographic Map. Scale: 1:62,500, 1:63:360 Scale [Also known as 15' map series: General Description: There were approximately 85 individual 15' topographic maps that covered some portion of the State of Arkansas. 3 software and was cached (pre-rendered) for the Web using ArcGIS Server 10. Type a value in the Map Scale box on the Standard toolbar. The scale is the ratio of distances on the map to distances on the ground. 5 The scale of the topographic is … A Five times larger than the orthophoto map B Five times smaller than the orthophoto map. The map is a representation of terrain detail. topographic mapping is 1:24,000. Add to Wishlist. This map product series, named "US Topo," is modeled on the now historical USGS 7. Site centered maps can be made at scales between 1:12,000 and 1:55,000. JOHNSON FOREST, Greenbrier County, WV (topographic map) Elevation Range: 2017' - 3244' +/-; Google Coordinates: LAT 37. What is a Topographic Map? Mapping is a crucial part of Earth science. A map must show the scale to which it was made. SUPPORT REQUIREMENTS: Topographic map, protractor, map pens, and a lensatic compass. This is added to the IMW zone number and another unique number is created. It provides a side view of the relief of the terrain along a line drawn between two locations on a topographic map. The Topo50 map series provides topographic mapping for the New Zealand mainland and Chatham Islands at 1:50,000 scale. Reading a Topographic Map. DRGs created by USGS are typically scanned at 250 dpi and saved as a TIFF. Geological Survey discontinued this series several years ago and many of the maps may no longer be available. It's free for areas up to 1 km 2 and over 200 whole city DXF files. Medium-scale topographic data dictionary. You precisely center your map anywhere in the US, choose your print scale for zoomed-in treetop views, or panoramic views of entire cities. The files have not been updated since that time, and many of the maps are more than 30 years old. 4 State the scale of the Orthophoto map as a word scale 3. Geologic maps display rock units and geologic features of a region of any size. Find the elevation and coordinates of any location on the Topographic Map. Thivierge and. The first is a ratio scale. (Scale is the relationship between distance on the map and distance on the ground. Map scale represents the relationship between distance on the map and the corresponding distance on the ground. Your map is your companion who helps you find distances and direction, helps guide you over and around obstacles, and sets you on course to your next water source or camp. Each map is identified by its latitude and longitude and is given a distinctive name, for example, "Upper Chesapeake Bay. Airborne Topographic Lidar Manual. These maps are modeled on the familiar 7. This application uses licensed Geocortex Essentials technology for the Esri ® ArcGIS platform. The Topo50 map series provides topographic mapping for the New Zealand mainland and Chatham Islands at 1:50,000 scale. Geological Survey DGS98-7 is a set of twenty-one (21) topographic base map images of the counties in New Jersey. 513 individual 1:250,000 scale topographic maps, and; 3,066 individual 1:100,000 scale topographic maps; This problem was partly solved by the development of a numbering system for the International Map of the World (IMW). 5 minute topographic quadrangles put out by the U. While the default list includes some of the most common map scales, such as 1:24,000 and 1:100,000, you may want to customize the list with your own scales and have them be listed with the others. 30 Best Photos Of Lake Ray Hubbard topographic Map. Individual topographic maps are commonly referred to as quadrangles (or quads), with the name of the quadrangle giving an idea of the amount of area covered by the map. free map of Shestakovo calibrated for Garmin. The series consists of a total of 1 913 sheets. Basic cartography activities IES Concepción Arenal 2. A topographic map provides the frame of reference upon which most geologic maps are constructed. 5 minute (1:24,000 scale) USGS Buffalo National River topo map as an Adobe PDF. Metadata for Digital Topographic Maps of Vietnam. The popular USGS topographic quadrangle maps (often called 'topos' or 'quads') are available for the entire state. USGS topographic maps come in a variety of scales. The topographical map and the orthophoto map must be handed over to the invigilator at the end of the examination session. A scale of 1:10 000 is a large scale and 1:50 000 is a small scale. On a map with a ratio scale of one inch to one mile scale would be represented as 1: 63,360. 1:24,000 Scale Compressed Topographic Map Images (1998) These are images of U. In addition to showing natural terrain, most topographic maps also feature symbols and markings for prominent man-made features and boundaries. The inner protractor is marked in degrees and the outer protractor is in mils. 1:24,000 Scale Topographic Map Images (1998) These are images of U. The first is a ratio scale. A global topographic map of Titan. Step 4: Make the map profile from your topographic map. Along with a full elevation map, 3 seperate maps of west, middle and east parts of the world are there. Below is a listing of the scales at which some of the more popular USGS maps are compiled. 01 meter coordinate precision). Show Less. Use this guide to understand the different scales found on maps in our map collection. Since 2002 Quality control of topographic maps inflicted to CGI and the. A topographic map provides the frame of reference upon which most geologic maps are constructed. Step 1: Select Area of Interset Draw polygon to select lidar products for area of interest. Georeferenced raster digital images are provided at a resolution of 300 DPI. How to Read Topographic Maps. Geospatial References. The USGS Topographic Map tile indices can be used to determine the 7. a topographic map. Although the moon is Earth's closest neighbor, knowledge of its morphology is still limited. JOHNSON FOREST, Greenbrier County, WV (topographic map) Elevation Range: 2017' - 3244' +/-; Google Coordinates: LAT 37. Alexandra Township, Johannesburg, South Africa. Surface height profiles along lines of latitude. 6 m) on the ground. Topographic profiles are usually "stretched;" this is done to better visualize the landscape How to calculate Vertical Exaggeration Divide the ratio horizontal scale (always given on topo map) by the ratio vertical scale (must find topo profile). Topographic maps serve as a reality check for the other maps, especially those that have been interpreted, such as the soil, geology and vegetation maps. The scale of the orthophoto map is five times smaller than that of the topographic map. Topographic Map Scale. PSM V72 D507 Topographic map of water sources and human settlement. This is added to the IMW zone number and another unique number is created. topographic mapping is 1:24,000. It covers the same area of land as sixteen 1:50 000 scale maps. Army Map Service 1965 (2. We've detected that you're using an ad content blocking browser plug-in or feature. The Office of Spatial Data Management provides an online free map service MapConnect. Final product i. 1:24,000-Scale Mapping Program Index Maps. It provides a side view of the relief of the terrain along a line drawn between two locations on a topographic map. These maps show topographic features including contours and elevation in meters, highways, roads and other manmade structures, water features, woodland areas, and geographic names. com/sharing/rest/portals/self?f=json status: 0. Home > Finding Information > PCL Map Collection > India and Pakistan AMS Topographic Maps U. Polygon Freehand Polygon. Or scroll down to browse the list of maps. Large Scale Maps Are used for tactical, administrative, and logistical planning. Each contour line shows the increase or decrease in elevation in relation to a fixed altitude, normally sea level. Each tile index contains the following attribute fields: Name - the name of the map OHIO_CODE - code usded by USGS TILE - the image tile name on FTP site.