An interchange crossroad with people walking on ground and vehicles traveling above and under the ground is provided. In a basic type, four layers are comprised which are an overpass, a mezzanine, a ground plane and an underpass from up to down, the overpass and underpass respectively allow vehicles traveling longitudinally and vehicles traveling transversely to go straight and make a turn, only vehicles on the same road give way to one another under traffic lights, and the overpass and underpass are provided with lateral parking horizontal wing spans of adjustable lengths. In a reduced and flexible type, the four layers are reduced to three layers, “only vehicles giving way to one another” is achieved, all the vehicles are centralized on either the overpass or the underpass and commanded by traffic lights. The entire crossroad zone of the ground plane layer has no vehicle and is used exclusively for citizens.