In this paper we combine the geographic variation of closely related language variants (‘dialects’) with the distribution of sound correspondences through the lexicon. One of the central problems with sound correspondences at the dialect level is that they are not very regular, especially when they are investigated in sufficient detail. Sound changes spread both through a language (e.g., from one word to another) and through the population of speakers (in our case through a population of villages with different dialects). Both processes happen at the same time, and the challenge is to reconstruct what has happened from a snapshot of synchronic data. The method described in this paper allows us to track the geographic spread of sound changes and the underlying patterns of linguistic diversity simultaneously. By combining the two, it is possible to detect areas of intensive linguistic contact and gain better insight into the mechanisms of language change.