Navigation Tip – Use a “finger scale”

Here’s a slick way to quickly measure distances in the field on a topographic map. Get out a 1:24,000 scale 7.5 minute topo map, and look at the scale bar at the bottom. Using different fingers, place them on the scale bar and see how much map distance one finger covers. For me, the width of my index finger is 1/4 of a mile at 1:24,000 scale. (Depending on your finger width, your mileage may vary.) Once you remember this number (“index finger = ¼ mile”), it is very quick to estimate distances from the map, simply by leapfrogging your index fingers side by side.

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Navigation Tip – Use a “finger scale”