ATRACTOR

Choose four cities in the map by moving points $A$, $B$, $C$ and $D$ to the desired location.

(In order to work, the points $A$, $B$, $C$ and $D$ should be chosen clockwise.)

To see the minimal (shortest) network of roads that links those four cities, please move the red dot until the points $X$ and $Y$ overlap. Only then the minimal network will appear automatically.