Control flags are often on the opposite sides of the control feature from the direction you are approaching and often the control feature is large enough to hide the flag. For that reason is typically best to look for the control feature itself rather than just looking for the control flag itself.
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"A normal course is made, but for each control, there are several other controls within the control circle. There is no code on the controls, so the runner must decide which control is the correct one by studying the map and the control description. Some kind of penalty (penalty loop running, time penalty etc.) is given for each wrong control."
"Focus on making each control easier by "prolonging the control". Prolonging the control means to find features close to the control which are wider than the feature the control is placed on, i.e. you can have a larger error in your compass course and still find the control easily. There are several variants of this training - also a theoretical exercise."