Posts made in October 2017

Gila Wilderness (Land Navigation)

Land Navigation: Map Colors

THE AMERICAN BACKPACKER

Topographical maps are a wealth of information.  Understanding the colors on a topo map allows you to get a better vision of what type of terrain you will encounter. Below are some of the basic colors you will find on a Topo map.

Basic Topo Map Colors

  • BLACK: Man-made areas (eg. buildings, small roads).
  • RED: Built up areas like cities.
  • BROWN: Terrain reliefs and contour lines.
  • GREEN: Vegetation, (Trees, Forests, etc.).
  • BLUE: Water, (Lakes, Streams, Creeks, etc.)
  • OTHER COLORS: They are explained in the legend.

 

Wind River Range

Land Navigation: Terrain Features

THE AMERICAN BACKPACKER

When looking at a Topographical Map you need to be able to identify terrain features to effectively navigate through a Wilderness Area. There are 5 Major and 3 Minor terrain features you need to know. This article will discuss those terrain features.

5 Major Terrain Features

HILLTOP

A Hilltop is an area of high ground from which the ground slopes down in all directions.


SADDLE

A Saddle is a low point between two areas of high ground.


RIDGE

A Ridge is high ground where the ground slopes in three directions and high ground in another.


VALLEY

A Valley is low-lying ground that has three directions of high ground and one direction of low ground.


DEPRESSION

 A Depression is a low point of ground or a sinkhole.

Topographical Depression

3 MINOR TERRAIN FEATURES

SPUR

A Spur is a Ground that Slopes downward and it protrudes out from the side of a ridge or hilltop.


DRAW

A Draw is where ground slopes upward on each side and toward the head of the draw.


CLIFF

A Cliff vertical slop or drop off.

Topographical Cliff

Knowing the above terrain features allows you to effectively understand and navigate using a Topographical map. Before you head into a wilderness area get a topographical map review the area you plan on exploring. Below is a video on the above terrain features that will give you a better explanation of terrain features on a Topographical Map.


Terrain Features (Video)

The American Backpacker

Land Navigation : The Lost Skill

THE AMERICAN BACKPACKER

Land Navigation is an essential skill that all Wilderness Backpackers need to know. Land Navigation is becoming a lost skill due to technological advances. In 1983, GPS (Global Positioning System) was made available to the public using a network of satellites. The first handheld units became available to the public in 1989.   Since then many Wilderness Backpackers have become too reliant on the use of GPS units and less reliant on basic land navigational skills.

I will be posting several articles on different topics and skills related to Land Navigation. My intent is to give you a basic knowledge and the necessary skills to navigate safely in a Wilderness Area.


An Overview Of Topographical Maps

Once you have decided on which Wilderness Area you plan on exploring the next step is to get a  topographical, (Topo) map. A topo map is a picture of the terrain you will encounter while on your backpacking adventure. This visual representation details terrain features such as elevations, hilltops, valleys, trails, and a host of other important information.

You should always have a topo map with you in a Wilderness Area. You should also know where on the map you are at all times. Topo maps can be purchased online or downloaded from various outdoor websites. Downloading a topo map is easy and it allows you to focus on a specific region.

I recommend using a waterproof paper when you print your map. I use Terra Slate waterproof paper that you can purchase on their website or on other online stores.  Printing out your topo map allows you to take a more condensed version of the map into the field as opposed to bringing out a large cumbersome foldable map.

Topo maps have legends on the bottom of the map.  A legend is the dictionary of the map giving you important information defining things on the maps. These symbols consist of but are not limited to roads, man-made objects, towns, trails, scales, etc. The scale in the legend will help you in determining linear distances.

Map Legend

The legend also provides you with a magnetic declination for the area you will be exploring. The magnetic declination is the variation between your compass bearing/azimuth and your map north or true north. I will explain further in another article on what magnetic declination is.

 Topo maps also have contour lines.  Contour lines are the squiggly lines on the map. Contour lines help you determine the elevation of the terrain you will navigate.  Between each line is an established distance in feet which will let you know if you are traveling up or down.  The darker/bolder contour lines are called contour index lines.  Contour index lines have a number associated with them.  That number indicates the elevation, (in feet), of that particular index line.



Topographical terrain does not change much and yearly revisions like street maps are not necessary. You should research the area online and call the local Ranger district for updates and more information on the area you plan on exploring. There may have been a fire, severe weather, or other man-made changes that may have altered a trail or a portion of the terrain that you will be traveling on. Ranger District staffin that area will be able to tell you about these changes so you can properly plan your adventure.

The articles I post will build your basic land navigational skills. My intent is to make you more proficient and confident while you navigate in a wilderness area.


Topographical Maps