PURPOSE: To easily make an stranger familiar with the area by clearly distinguishing an intersection by displaying the same intersection with the same name.

CONSTITUTION: When a given point in a P intersection is taken as P, the point P is mathematically taken as plane coordinate and can be displayed as P [X, Y] (X: horizontal direction, 7.0≤X≤8.0, Y: vertical direction, 2.0≤Y≤3.0). For example, P[7.5-2.5] intersection (being the intersection of two points and five chome of seven points and five jo) is decided by taking the point P as the center point. Like points F and Z, it is not necessary to be the center point at all times, but the relative position of each point should be the same. The decimal parts of the four summits of the intersection P is shown by zero. For example, the upper left summit is Q[7.0-3.0]. Further, it is more effective when giving a sign of inequality [large (>), small (<)], and upper and lower sign of inequality [upper large (V), upper small (Λ)] to the intersection sings displayed by decimal values.