1. A 3D map display system for displaying a 3D map on which a ground surface and a plurality of features are represented three-dimensionally, comprising: a map database for storing map data representing a 3D shape of the ground surface and the features; a first drawing unit for drawing the ground surface and the features by executing depth determination by referring to the map database, thereby generating a first drawing result; a second drawing unit for drawing at least one target feature, the target feature being a feature in which at least a part thereof is hidden by the ground surface or other features in the first drawing result, by overwriting the target feature on the first drawing result using the map data without executing depth determination with respect to the first drawing result, thereby generating a second drawing result; and a third drawing unit for drawing at least one specified feature among the features by superimposing the specified feature over the target feature in the second drawing result without executing depth determination with respect to the second drawing result.