This paper documents the many taxometric and cartographic achievements of the Salzburg school of dialectometry. The paper discusses the following topics: (1) problems of measurement of linguistic atlas data (with particular consideration of Romance linguistic atlases), (2) establishment of the data matrix, (3) choice of the similarity index (Relative and Weighted Identity Value), (4) generation of the respective similarity and distance matrices, (5) their subsequent cartographic exploitation, which encompasses the following cartographic tools: similarity maps, parameter maps, dendrograms (and their spatial projection), and correlation maps. The ultimate purpose of these highly sophisticated cartographic techniques (choropleth and isopleth maps) is to increase our knowledge of the complex mechanisms of the dialectal management of space by man. From a methodological point of view our paper deals with problems related to (Romance) dialectology and linguistic geography, historical linguistics, numerical classification, statistics and statistical cartography. The examples are drawn from the French linguistic atlas ALF (Atlas linguistique de la France) published by Jules Gillieron and Edmond Edmont (Paris: Champion, 1902-1910, 10 volumes) more than one hundred years ago. The taxometric calculations and their respective visualizations are realized by a powerful computer program called 'Visual DialectoMetry' (VDM), created by Edgar Haimerl (Blaustein, Germany) between 1997 and 2000 in Salzburg, which is freely available for research purposes.