Topographic Maps 101

The intricate details on a topographic map can be befuddling, even frustrating, if you are learning while out in the backcountry. But once you get familiar with the markings and symbols, reading maps will become a friendly aid, rather than a dreaded assignment.

Topographic Maps Grid System

Lines of latitude run parallel to the equator (east and west), and lines of longitude run perpendicular to the equator (north and south). These lines form a pattern of squares across the surface of the earth like a checker board.

One square, formed by lines of longitude and latitude, measures 90 degrees x 90 degrees. Degrees are further subdivided into minutes and seconds.

? 1 degree = 60 minutes
? 1 minute = 60 seconds

The important thing to understand, when we look for a topographic map for our hiking adventures, is that it will be located within this larger context of degrees, minutes, and seconds. Fortunately, it will also, usually, be identified with a place name.

An alternative method of notation within the Geographic Coordinate System is the decimal degree system. In the decimal degree system, minutes and seconds are replaced by a percentage of a degree, expressed as a decimal up to four places long. It is often used for Geographic Information Systems (GIS) applications,

Topographic Maps Scale Explained

A topographic map lists its scale in the margin or legend. The scale is the relationship between distances on a map and the corresponding distance on the ground. For example, a map with a scale of 1:50,000 means that 1 unit of measurement on the map equals 50,000 equivalent units on the ground.

Units can be in inches, feet, centimeters, or meters, depending on what scale map you are looking at and what measuring system the country uses. Most USGS maps are 1:24,000, also known as 7 ˝ minute maps. On this map, 1 inch = 24,000 inches on the ground. In Canada, most hiking maps are 1:50,000 scale, where 1 cm = 50,000 cm on the ground.

A small scale map (ex. 1:100,000) covers a large area; it shows less detail with fewer features. A large scale map (ex. 1:10,000) covers a small area; it shows great detail and small features. A 1:2,500, large scale map would show individual houses and street lights.

Topographic Maps Symbols and Colors

The symbols and colors used on Topographic maps are fairly straight forward:

? Black - man-made, "cultural," features such as roads, buildings, etc. It is also used to show geographical names (toponymy), certain symbols, geographic coordinates, precise elevations, border information and surround information.

? Blue ?water, lakes, rivers, streams, etc. The names of bodies of water and water courses are also shown in blue, as are magnetic declination and UTM (Universal Transverse Mercator) grid information.

? Brown - contour lines, contour elevations, spot elevations, sand.

? Green - areas with substantial vegetation like a forest, orchard, or vineyard

? Grey - used on the back of the map where the different symbols and a glossary of terms and abbreviations can be found.

? Orange - unpaved roads and unclassified roads and streets.

? Purple - features added to the map since the original survey. These features are based on aerial photographs but have not been checked on land.

? Red - major highways; boundaries of public land areas. A red tint is used to show an urban development.

? White - areas with little or no vegetation; also used to depict permanent snowfields and glaciers

Topographic Maps Glossary

? Bearing - Angular direction expressed in degrees.

? Contour Lines ? A line on a map joining points of equal elevation. These lines are used to illustrate relief on a map.

? Distortion - The difference in shape between the actual curved surface of the earth and the flat representation of a topographic map.

? Grid - A system of horizontal and vertical lines that provide coordinates for locating points on an image.

? Magnetic Declination - The angle between magnetic north and true north, expressed in degrees and minutes, east or west from true north.

? Magnetic North - The direction your compass needle points.

? Projection - A method by which the curved shape of the earth is represented on a flat surface, overcoming distortion.

? Relief ? The variations in elevation of the earth's surface.

? Scale ? The relationship between distance on a map and the corresponding distance on the ground. For example, a map with a scale of 1:50,000 means that 1 unit of measurement on the map equals 50,000 equivalent units on the ground.

? Topographic Map ? An illustration of the earth's different elevation levels by means of contour lines. They present both natural and manmade features.

? True North - Direction of the northern rotational axis of the earth ? the North Pole.

Outdoors Adventurer, Writer and Webmaster Will Robertson lives with his family in Little Rock, Arkansas.

Explore the best hiking vacations and gear on the planet at: http://www.hiking-vacations-and-gear.com

In The News:


pen paper and inkwell


cat break through


Campsite Meal Planning and Recipe

Hello Again,Today we will be talking about meal planning. Meals... Read More

The Best Safari Company for Your Safari Trip - Heres How To Choose

Which is the best African safari company for my safari... Read More

Ten Skills - A Backpacking List

Have you ever had a backpacking trip that was a... Read More

Tamil Nadu ? A potpourri of culture and festivity

Tamil Nadu is a delightful anachronism. With a rich culture... Read More

Lake Winnipesaukee ? The Smile of the Great Spirit

Lake Winnipesaukee is the largest and one of the deepest... Read More

Japanese Garden of Monaco

Have you ever seen an authentic Japanese garden? Well, I... Read More

Comal White Water or More Blue Green

White Water on the Comal river in Central Texas is... Read More

RV Vacations: Ten Tips

Perhaps you have wondered about taking an RV vacation. It... Read More

Be Sure to Buy the Best Discount Camping Gear Before Going on that Family Adventure

When you're on the Internet looking for discount camping gear,... Read More

Review: Russell Shortos The Island At The Center Of The World

Up to now the preponderant view held by many historians... Read More

River Cruise in Bangkok ? Sightseeing on the Chao Phraya

A river cruise in Bangkok gives an insight to the... Read More

Code of Conduct for Outdoor Enthusiasts

My favorite outdoor related quote comes from John Muir, the... Read More

What You Need to Know About - Camping Vacations

Camping is a delightful and adventurous way to spend your... Read More

Boondocking America

Boondocking is fun! Boondockers go anywhere they want, at any... Read More

How to Repair an Inflatable Boat

The owner can attempt small inflatable boat repair if factory-gluing... Read More

Tanzania Safari Top Five National Parks and Game Reserves

Ask about perfect wildlife destinations and a Tanzania safari will... Read More

The Royal Barge Procession ? Splendor on the Chao Phraya River

The Royal Barge Procession in Bangkok, conducted on very rare... Read More

The Benefits of One Day Hiking Trips

Do you like to take one day hiking trips? Do... Read More

Visiting Whistler in Summer

It is the end of the season for the year... Read More

Ten African Safari Tips That You Must Know Before You Go

1. Take the early morning drives on safari even though... Read More

Planning Your Own Gorilla Safari Will Save You Money - Heres How

Going on a gorilla safari must rank as one of... Read More

Greek Food

A meal in Greece is highlighted with a selection of... Read More

A Torrent of Influences ? Tourism in Goa

Sun, Sand and Surf ? an apt description for Goa?... Read More

How To Buy a Used RV - Part 2

The key to getting a good bargin, instead of a... Read More

The Great Outdoors is to be Explored and Loved in all its fullness

The thing with enjoying the great outdoors is seeing aspects... Read More

Canoe Trip with Nature

A canoe trip is a great way to appreciate Nature!A... Read More

San Diego Beach Hikes ? Cardiff to Carlsbad

San Diego offers a bevy of interesting hikes. With the... Read More

Hiking in the Forest Knowing When to Slow Down

One morning in mid summer, I headed out for some... Read More

Mammoth Cave: One of the Most Beautiful in Our National Park System

Directly south of Louisville, just off Interstate 65 and not... Read More

Find Outdoor Camping Gear Online at Great Discount Prices

Before you take off on that great outdoor adventure, be... Read More

The Classy Way to Do WA

Western Australia ? South-West Coast driving holiday. Great Australian Road... Read More

Ultralight Backpacks - The Lightest

Why ultralight backpacks? Devotees of ultralight backpacking know you reduce... Read More

Hiking Shoes Versus Hiking Boots

Hiking shoes versus hiking boots? Hiking shoes win. Okay, next... Read More