The article deals with the conceptual design of bridge crossings, which are the most important component of the roadway network. Classification of types of river valleys are described, suggestions on the use of the Dijkstra's algorithm for the automated design of bridges are given. The text gives valuable information about the cost parameters of the bridge construction for each type of the river valley. A methodology of appraising is based on the legislation of the Russian Federation. Engineering, geological and land aspects of geoinformation analysis are considered. A methodology for computer-aided design that makes it possible to find the most advantageous options of linear structures is developed. Linear sections and artificial structures – bridge crossings are emphasized.