When is an intersection used in land navigation?

• A. To discover the grid of an unknown point that is inaccessible due to enemy targets or danger areas
• B. To determine your own position by using the grid azimuths of two well-defined locations on the map
• C. To measure distance between two known points
• D. To align your compass with the sun

Answer: (A)

Intersection is used to locate an unknown point by drawing lines of position from two known locations. From each of those known points you determine the direction toward the unknown point and plot a line on the map along that bearing (using grid azimuths for accuracy). The point where the two lines cross is the grid location of the unknown point. This method is particularly helpful when the target point can’t be reached or observed safely, such as being behind enemy targets or in dangerous terrain. Using the map’s grid azimuths keeps you aligned with the coordinate system, and you can convert to magnetic bearings if needed. This approach differs from other techniques like determining your own position from two known points, or simply measuring distance between two points or aligning a compass with the sun.