Using high resolution laser scanners, it is possible to create consistent 3D point clouds of large outdoor environments in a short time. Mobile systems are able to measure whole cities efficiently and collect billions of data points. Such large amounts of data can usually not be processed on a mobile system. One approach to create a feasible environment representation that can be used on mobile robots is to compute a compact polygonal environment representation. This paper addresses problems and solutions when processing large point clouds for surface reconstruction.