In this paper, I introduce methodologies to tap corpora for exploring aggregate linguistic distances between dialects or varieties as a function of properties of geographic space. The paper describes the different steps necessary to obtain an appropriate corpus-based dataset (a so-called ‘distance matrix’), and subsequently discusses several cartographic visualisation techniques–network maps, continuum maps and cluster maps–to project aggregate linguistic relationships to geography. In addition, the paper sketches some statistical methods to quantify these relationships. By way of example, a case study draws on the Freiburg Corpus of English Dialects–a major dialect corpus in which more than thirty traditional dialects of English from all over Great Britain are sampled. With a focus on regional variation in morphosyntax and on the basis of text frequencies of several dozen features, the study probes joint linguistic variability between the dialects sampled in the corpus.