Getting comfortable with reading topographic maps
Once I learned to read and interpret topographic maps, a new world opened to me. Identifying the difference between a spur and a re-entrant, your ability to navigate your way around the world that surrounds you becomes so much clearer.
But let’s take a step backwards here for a moment…
What does a topographic map show us?
A topographic map shows you the world and its physical features in several ways.
Early topographic maps showed hills and valleys with different shadings or striations to show shadows and slopes. But today, these features are shown in the form of contour lines.
Introduction to Contours
Contour lines are lines on the map that join points on the Earth’s surface that are the same height above sea level.
Maps with lines of contour indicate the presence of hills, mountains, valleys, steep tracks, flat areas, boggy areas, and the all important cliffs – to name a few.
Additionally, they point out prominent features such as mountains. Knowing these mountains (and hills) are there and the gradient of the mountain or hill, not only grants immediate ‘Hero status’ at the campsite, it also allows you to get your bearings and develop a relationship with what’s around you.
Whilst there are many mapping tools available on the market, featuring contour lines and other overlays, ‘Topo Maps+’. deserves a closer inspection.
Two functions of this app relate to the elevation data held on in the system.
This elevation data allows for two very interesting enquiries, namely:
- Line of Sight – where the direction you’re pointing your device is shown as a blue line on the map; and
- Elevation Profile – where you can see a cross-section of the terrain immediately ahead of you and see the ups and downs in a graphical form.
So what does this data mean?
Note: These features are in the Pro version.
What am I looking at?
If you see a hill, mountain or feature in the distance, the Line of Sight function allows you to rotate your device to point at that feature and identify it from the available information. It allows you to see on the scale how far away it is.
To work out the Elevation Profile use the information of contours (heights) and distances available within Topo Maps+. Plot the heights in graphical form with their respective distances along the Line of Sight. For those uncomfortable with contours, you can clearly see the terrain you will need to cross if you take that line.
Topo Maps+ takes this one step further, and outlines in red the features you will see from your selected position. This is because you can’t see over hills and into the valleys below. This allows a much clearer picture of what’s in front and around you.
Finding Mount Flinders, SE Queensland, Australia
Whilst on a trip down to Darlington Park Camping Grounds recently (refer https://campandtravel.com.au/darlington-park-scenic-rim-qld/) I took the opportunity to use the Line of Sight function to correctly identify a feature I saw in the distance.
Feedback to Topo Maps+
Two comments from me to Topo Maps+ to improve these functions are: (1) plot the Elevation Profile a short distance behind me at my point of view. I suggest this because the resultant graphical image has your location hard up against the edge of the screen. While a user set distance may add too much complexity to the software perhaps a set 100 metres or so would help.
(2) the direction of the line of sight (travel) be clearly stated or shown on the elevation profile to avoid misinterpretation. In the screenshot below the line of sight is right to left (east to west) but the cross-sectional image is left to right. I do note that a corresponding blue circle appears at my position. An arrow may add clarity.
Topo Maps+ has many extra exciting functions and the company seems keen to continually enhance the product and communicate with users. My suggestion to the readers of this blog is to download the free app and give it a whirl. This will ensure you are on Topo Maps+ mailing list, which will keep you current on their upgrades and any information relevant to this topic.
Map reading is a skill. Have fun with it and stay safe.