1. A vehicular travel course searching apparatus for identifying a course connecting two selected points on a road map depicted on a display screen by using selected functions for evaluating a course of travel, said functions including parameters representing a plurality of travelling costs including at least a travelling distance cost and a road width cost, each parameter having a variable weight coefficient, said course searching apparatus comprising: a signal processing unit electronically coupled to a display, a data entry device, a travel path memory, and a memory read-out device, said memory read-out device being electronically coupled to a road map data memory; and said signal processing unit including first processing means for identifying a main course formed by a main road between two points adjacent to said selected points, said first processing means processing data of a main road map using a first selected function for evaluating a travelling course and being initialized such that increased weight is assigned to a road width cost parameter; and second processing means for identifying course components connecting, respectively, said selected points with said identified main course, said second processing means processing data representing a detailed local road map using a second selected function for evaluating a travelling course, and being initialized such that increased weight is assigned to a distance cost parameter.