Topographic maps have a map legend (or key). The map legend lists the features shown on the map with their matching symbols. They also have location reference systems. These include longitude, latitude and a coordinate grid, so you can accurately work out the position of mapped features.
What are most important features of a topographic map?
topographic map, called provisional, some symbols and lettering are hand- drawn. U.S. Department of the Interior U.S. Geological Survey Reading Topographic Maps Interpreting the colored lines, areas, and other symbols is the fi rst step in using topographic maps. Features are shown as points, lines, or areas, depending on their size and extent.
What are features on a topographic map?
Topographic maps are detailed, accurate graphic representations of features that appear on the Earth’s surface. These features include: cultural: roads, buildings, urban development, railways, airports, names of places and geographic features, administrative boundaries, state and international borders, reserves.
What is the legend on a map?
A map legend or key is a visual explanation of the symbols used on the map. It typically includes a sample of each symbol (point, line, or area), and a short description of what the symbol means. For example, a short segment of a blue sinuous line may be labeled 'rivers'.
What maps are similar to topographic maps?
Wabamun Lake Hydrographic Chart. Bathymetric maps are similar to topographic maps, except they show contours of depth in a lake or reservoir, rather than contours describing the height of a mountain. Bathymetry is a useful technique for Fisheries management to segregate our data collections and analysis, but is even mo
Does a topographic map have a legend?
Although many symbols used in different maps are similar, there is no one standard international legend for topographic maps. Below you can find the Canadian NTS and USGS topographic maps' legends.
What are the symbols for a topographical map?
Topographic maps use symbols to represent natural and human constructed features found in the environment. The symbols used to represent features can be of three types: points, lines, and polygons. Points are used to depict features like bridges and buildings.
Why is it important for a topographic map to have a legend?
Topographic maps have a map legend (or key). The map legend lists the features shown on the map with their matching symbols. They also have location reference systems. These include longitude, latitude and a coordinate grid, so you can accurately work out the position of mapped features.
Where is the legend on a map?
Legends usually appear near the bottom of a map or around the outer edges, outside of or within the map. If you're placing the legend within the map, set it apart with a distinctive border, and take care not to obscure important areas of the map.
What are the five map symbols?
Let's get started!Title. It may seem a simple place to start, but every map needs a title. ... Map Scale. To put the information of the map into context, cartographers must add a map scale. ... Map Key (Map Legend) ... Compass Rose. ... Latitude and Longitude.
What are the 3 types of map symbols?
There are three types of map symbols:Point Symbols= buildings, dipping tanks, trigonometrical beacons.Line Symbols= railways, roads, power lines, telephone lines.Area Symbols=cultivation, orchards and vineyards, pans.
What is the purpose of a map legend?
A map legend is a description, explanation, or table of symbols printed on a map or chart to permit a better understanding or interpretation of it. Map legends usually contain information on the map scale as well.
What is an example of a map legend?
Definition: A key or legend is a list of symbols that appear on the map. For example, a church on the map may appear as a cross, a cross attached to a circle, a cross attached to a square. A church symbol with a square means that the church has a tower, while a circle means the church has a spire.
What is a map legend and why is it important?
A map key or legend is an essential part of the map. It explains what the symbols on the map mean and allows you to make sense of the map. Maps are very valuable tools that can be used to easily show things that would otherwise be difficult to understand.
What is legend in geography?
A legend in geography is an area set aside on a map that has a list of symbols, shapes, and colors. These symbols, shapes, and colors have special meaning and are defined so that a person reading a map can understand the map, i.e. point, line and polygon symbols.
What is the difference between a map key and a legend?
These terms are typically used interchangeably, but sometimes a map includes both a key and legend. In these cases, the key contains the list of symbols used on the map, and the legend includes the scale, abbreviations, and compass rose to show the cardinal directions.
How are legends on a map made?
When creating a map, include a clear and legible legend that is positioned in a visible space. Typically, map legends are placed in one of the four corners of the map so that they can be quickly referenced. Draw a box surrounding the legend to clearly separate it from the rest of the map.
What are the symbols used in a map?
Map symbols may include point markers, lines, regions, continuous fields, or text; these can be designed visually in their shape, size, color, pattern, and other graphic variables to represent a variety of information about each phenomenon being represented.
What are the 5 colors on a map?
Blue: lakes, rivers, streams, oceans, reservoirs, highways, and local borders. Red: major highways, roads, urban areas, airports, special-interest sites, military sites, place names, buildings, and borders. Yellow: built-up or urban areas. Green: parks, golf courses, reservations, forest, orchards, and highways.
How do you read a topographic map?
0:553:48How to Read a Topo Map - YouTubeYouTubeStart of suggested clipEnd of suggested clipAnd most maps have either a 40 or 80 foot contour interval if your map has an 80-foot interval thatMoreAnd most maps have either a 40 or 80 foot contour interval if your map has an 80-foot interval that means that each contour line is 80 vertical feet away from the next.
What are the conventional symbols?
Solution: The symbols and signs which are accepted by all are known as conventional symbols. The various tools in the conventional symbols are the combination of dots, lines, colours and alphabets. They can be used to depict features like cities, roads and railways.
Where is the legend on a map?
The legend can be located along the borders, below the map, or on the back of the map. Although many symbols used in different maps are similar, there is no one standard international legend ...
Why are symbols used in maps?
Symbols are used in topographic maps to identify cultural and natural features. Symbols come in different shapes, sizes and colors to uniquely identify such features on the map.
What are natural features?
Natural features may include water (rivers, streams, lakes, wetlands and swamps, rapids), relief (mountains, valleys, canyons, and other landforms,...), vegeta tion (forested areas, cleared areas, orchards, ...). Toponomy or feature and place names are added to provide textual information about features. Gridlines and contour lines on the map are ...
Is there a legend for topographic maps?
Although many symbols used in different maps are similar, there is no one standard international legend for topographic maps. Below you can find the Canadian NTS and USGS topographic maps' legends. The margin of the map contains other important information such as map scale, north arrow, declination diagram, datum, publisher, date, etc.
What are the characteristics of a topographic map?
A map is a representation of the Earth, or part of it. The distinctive character- istic of a topographic map is that the shape of the Earth’s surface is shown by contour lines. Contours are imag- inary lines that join points of equal elevation on the surface of the land above or below a reference surface, such as mean sea level. Contours make it possible to measure the height of mountains, depths of the ocean bottom, and steep- ness of slopes. A topographic map shows more than contours. The map includes symbols that represent such fea- tures as streets, buildings, streams, and vegetation. These symbols are con- stantly refi ned to better relate to the features they represent, improve the appearance or readability of the map, or reduce production cost. Consequently, within the same series, maps may have slightly dif- ferent symbols for the same feature. Examples of symbols that have changed include built-up areas, roads, intermittent drainage, and some letter- ing styles. On one type of large-scale topographic map, called provisional, some symbols and lettering are hand- drawn.
How are topographic contours shown?
Topographic contours are shown in brown by lines of different widths. Each contour is a line of equal elevation; therefore, contours never cross. They show the general shape of the terrain. To help the user determine elevations, index contours are wider. Elevation values are printed in several places along these lines. The narrower intermediate and supplementary contours found between the index contours help to show more details of the land surface shape. Con- tours that are very close together represent steep slopes. Widely spaced contours or an absence of contours means that the ground slope is relatively level. The elevation difference between adjacent contour lines, called the contour interval, is selected to best show the general shape of the terrain. A map of a relatively fl at area may have a contour interval of 10 feet or less. Maps in mountainous areas may have contour intervals of 100 feet or more. The contour interval is printed in the margin of each U.S. Geological Survey (USGS) map.
How to contact USGS for topographic maps?
For more information about topographic maps produced by the USGS, please call: 1-888-ASK-USGS or visit us at http://ask.usgs.gov/
What color are the lines in a map?
At one time, purple was used as a revision color to show all feature changes. Currently, purple is not used in our revision program, but purple features are still present on many existing maps.
What are the points symbols used for?
Various point symbols are used to depict features such as buildings, campgrounds, springs, water tanks, mines, survey control points, and wells. Names of places and features are shown in a color cor- responding to the type of feature. Many features are identifi ed by labels, such as “Substation” or “Golf Course.”
What does "shoreline apparent" mean?
Shoreline Apparent (edge of vegetation)*** Indefi nite or unsurveyed
Where is the legend on a map?
3. Read Your Map Legend —The map legend, usually found at the bottom of the map, helps you identify things like road classification, boundaries, coastal features and contours. Reference the U.S. Geology Survey’s guide to topographic map symbols for all the details on what the symbols in your legend mean.
What is a Topographic Map?
In addition to showing basic geographic features — roads, lakes, rivers, etc. — topographic maps also show terrain. They help us visualize elevation and give us a better idea of the hills, mountains and valleys in the area. To put it another way, topo maps can help us visualize our three-dimensional world in two dimensions.
How to master topography?
The best way to master topography is to study a topo map of an area you know well, whether it be your neighborhood or a famous landmark like Denali National Park. The U.S. Geology Survey has a topographic map database that you can use to pull maps of specific regions. Happy exploring!
What do the colors on a map mean?
c. Colors and Patterns — Your map’s legend should also indicate what each color represents. In general, with topographic maps, darker colors mean denser vegetation and lighter ones indicate sparser vegetation. Water features are represented in blue. Sometimes, patterns (such as small dots or lines) are used to indicate surface features, such as sand, mud, gravel or levees.
What is the name of the line that features elevation?
a. Index Lines —Typically, every fifth contour line is thicker than the rest and features the elevation written somewhere on the line itself. The thick lines are known as index lines and can help you determine specific elevations.
What are contour lines?
1. Learn About Contour Lines — Contour lines are the squiggly lines of topo maps that indicate elevation. Essentially, they connect geographic points that share the same elevation. The lines that are closer together indicate a fast-changing elevation (a steeper slope), while lines that are further apart indicate a slower-changing elevation (a more gradual slope). When you see lines that create a small circle with thin-spaced lines surrounding it, it is probably a high mountain peak. Once you’re practiced reading contour lines, you’ll be able to easily spot mountain peaks, ridgelines, plateaus and more.
What is the legend on a map?
The legend also lists key data like the map’s scale, contour- and index-line intervals, grid systems (used for more advanced navigation) and magnetic declination (needed to set up your compass).
What is the gold standard for topo maps?
The U.S. Geological Survey (USGS) used to be the gold standard for topo maps. Covering the entire country, its maps consisted of rectangular areas of land called quadrangles (“quads” for short).
What do contour lines indicate?
Contour lines also indicate the shape of the terrain. Roughly concentric circles are probably showing you a peak, and areas between peaks are passes. Studying a topo map of a familiar area is a great way to learn how to match terrain features with the contour lines on a map.
What does a circle with a tick mark on it mean?
Every once in a while, a circle indicates a depression rather than a peak. A circle with tick marks inside it indicates a depression, rather than a peak. You should also see elevations decreasing as you get near the depression.
What does green mean on a map?
It’s loaded with map-reading clues and navigational data. Start by studying what each line, symbol and color means. Generally, green indicates denser vegetation, while light or colorless areas suggest open terrain. And, as you’d expect, streams and lakes are shown in blue.
Can you use a trail map for navigation?
Simple trail maps are useful for trip planning but NOT for navigation in the field. Topographic maps go further, giving you the power to visualize three-dimensional terrain from a flat piece of paper. The feature that makes this possible is contour lines:
What does the legend of a topographical map mean?
The legend of a topographical map, like on any other type of map, will let you know what symbols, colors, and different types of lines represent, from rivers and roads to campgrounds, sno-parks, and waterfalls. The legend will also include other data ...
What does a topographic map tell you?
Not only does a topographic map indicate where elevation changes occur in the landscape , it will also tell you how steep or graduate those changes will be. If a map with a 20 foot contour index illustrates a landmass with a series of ten tightly spaced concentric lines, you can expect that 200 foot elevation gain to occur more rapidly than ten contour lines of the same scale being drawn over a broad area of the map.
What is the magnetic declination on a topographic map?
The other feature that makes topographic maps especially handy for hikers is magnetic declination. This is how you can adjust for variances between true north and magnetic north that can lead you off course. No matter how far magnetic north has separated from true north, finding magnetic declination (the angle between magnetic north and true north) can be found using the legend on your topographic map, as well as by using tools like the NOAA magnetic declination calculator.
How to read a topographic map?
A topographic map can be easy to read once you know the details. First, look for the map’s scale, which will let you know how much detail the map contains. The scale on any topographic map will tell you how many miles, or fractions of a mile, one inch represents. The smaller the scale, the more detail the map has.
What are contour lines on maps called?
In addition to those main contour lines— which are usually bolder than others on the map, and are called index lines — you may also find supplementary contour lines on your map that show smaller increments of elevation gain for added detail.
What instruments did surveyors use to measure altitude?
It was a tall order. Surveyors had to do much of the measurement work by hand, using aneroid barometers to calculate altitude, as well as steel tape measures and compass traverses for spatial distances.
Is Magnetic North wandering around?
Researchers are still trying to sort out why magnetic north is wandering around like the hikers its supposed to guide. But one thing’s for sure— knowing a full range of navigational skills, including how to read a topographic map, will help you stay on course no matter what the earth’s electromagnetic field, or the weather, or the terrain, is up to.
1. What is a topographic map?
A topographic map is a map that tells you the type of terrain in which you’ll be traveling.
3. How do contour lines describe terrain?
The feature of topographic maps that makes it possible to see the terrain is the contour line.
4. How do you identify features with contour lines?
Contour lines show more than just the steepness of a slope or the elevation of a peak.
5. Where should you get topographic maps?
If you’re looking for a topographic map for your next trip, check out the sites below.
7. What do colors define on topographic maps?
Some legends define what different colors represent on the maps, so you should always look at the legend first.
9. What should you know about map grids?
Many topographic maps have grid lines with the numbers 1-36 written in the middle of each box.
Final Thoughts
Understanding how to read a topographic map is a great skill to have — especially if you’re planning to hike in the backcountry or live off-grid.
