Systems and methods for simplifying a three-dimensional mesh providing a three-dimensional model, such as a three-dimensional model of a cityscape, are provided. In particular, mesh simplification techniques can preserve important structural shapes in the original three-dimensional mesh. Important features in a representation of a city scene or other scene can be represented by structural edges (e.g. building outlines, bridges, curved structures such as curved highway overpasses, etc.). These structural edges can be detected and a representation of the structural edges can be constructed in the mesh. The mesh can then be simplified using the structural edges as high-level simplification criterion such that the structural edges are preserved during simplification.