In one or more embodiments, techniques are provided for modeling overhead line structures of electric railways that utilize a flexible, reusable structure template to automatically generate a 3D model of the overhead line structure. Each structure template includes a set of points that represent joints of the overhead line structure and components that represent elements of the overhead line structure. A feature definition of each joint and component includes properties, constraints and cell mappings. By mapping key points of reference lines for an overhead line structure to key points in an applicable structure templet for the overhead line structure, and applying the constraints and, in some cases the cell mappings, a 3D model of the overhead line structure is automatically generated. The 3D model may be a “low detail” stick representation for fast modeling, or, using the cell mappings, a “high detail” cell-based representation for very realistic modeling.