Abstract In this paper we present an experimental study of the statistical and topological properties of the Webgraph. This work has required the development of a set of external and semi-external algorithms for computing properties of massive graphs, and for the large scale simulation of stochastic graph models. We use these algorithms for running experiments on a large crawl from 2001 of 200M pages and about 1.4 billion edges made available by the WebBase project at Stanford [], and on synthetic graphs obtained by the large scale simulation of stochastic graph models for the Webgraph.