Research on colour in Roman Pompeii has so far dealt almost exclusively with interiors. As part of a larger project on Pompeii's urban space this study deals with the exterior colours of facades and pavings. Using as source material the existing remains of the town, excavation reports and artistic and other reproductions, we have tested the hypothesis that the colour character exhibited in the well-known and colourfully illustrated findings of Vittorio Spinazzola is also valid for the rest of the town. This hypothesis was supported for some streets and clearly contradicted for others. We have found certain patterns regarding colour and status, function and traffic and identified a number of typically different colour characters for different types of streets.