How to Read a Topographical Trail Map
Maps, generally speaking, have been around since the times of Babylon. Though they’ve evolved over time, the basic concept remains the same: We must know where we are and where we’re going.
When it comes to the outdoor world, a person can easily look at a globe or a standard map of the country they intend to explore and point out their planned destination. Perhaps you point out a location in the Rocky Mountains of Montana. You will imagine forests and waterfalls and wildlife aplenty. And, yes, others will be aware of your general location. You will be aware of your general location. But is that enough?
While it’s easy to idealize an outdoor situation as being beautiful and freeing for the spirit, a reality check will tell you that the venture will likely be much more challenging.
This is where the topographical trail map comes in handy for navigation. It provides detail pertaining to the types of terrain, landmarks, and landscapes you may be facing. It allows you to be aware of what to expect and, therefore, you can plan accordingly. Below, the basics of reading a topo map are outlined.
Lines on the Paper
The contour lines on a topographical map are designed to give a three-dimensional representation of the terrain you’re exploring.
First, they show the elevation of an area. Points that connect to one another have the same elevation. The closer two contour lines are to one another, the steeper the slope. The farther apart they are, the lesser the slope.
In addition to elevation, the contour lines give a rough idea of the terrain’s shape!
Index Lines
The thicker/darker contour lines you see on the topo map are called Index lines. They occur at every five lines. Here, the precise elevation is noted.
Contour Intervals
The same amount of elevation is gained between each contour line on the map. Most often, maps have either an 80ft interval or a 40ft interval between contour lines.
Recognizing Terrain Features
Aside from the basic elevation information provided by the contour lines, the shapes and patterns the lines are organized into can help you identify specific features in the terrain such as depressions, cliffs, valleys, gullies, ridges and peaks.
Depressions and peaks are similar on a topo map. They both consist of large circles with the circles inside them gradually getting smaller. The contour lines of depressions, however, have tick-marks conveniently placed within them.
Cliffs are represented by extremely close-knit contour lines. Gullies and valleys are represented by either U-shaped or V-shaped patterns of contour lines.
The way different features are displayed on topographical maps is best understood if you’ve got a map right in front of you. With practice observing the way the contour lines are shaped and organized, you’ll become much quicker to grasp the information.
Map Scale
The map scale shows the ratio between the distance on the paper map in front of you and real-life distance. In example, 1 inch on the map could be equivalent to half a mile on the ground.
Map Key
The map key is an area on the map that expresses the meaning of different symbols, shapes, lines, and colors. Campgrounds, picnic areas, parks, lookouts, shelters, bodies of water and different types of terrain.
Practice, Practice, Practice!
Like any hobby or discipline, mastering the topographical map is a matter of practice. Just for fun, take a hike in an area you’re already familiar with. Bring a topo map of the area with you.
Compare the contour lines and features of the map with what you’re seeing in the present moment. You’ll begin to recognize how the features placed on the map are similar to that of the real world. Once you get the hang of it, you’ll be armed and ready for brand-new destinations!