As there is relatively little archive material in the older files (up to 1783) of the Archives of Slovenia concerning the Tolmin region, it was possible to analyse the existing documents in greater detail. Emphasis has been placed in this article on the file "Provincial Diets, 1st Registry Office" and the documents on the tollhouse in Bača in the 16th and 17th century this file contains. Other interesting sources are stored under the headings: "Landgrave's Office" (German: Vizedomsamt), covering the period up to the middle of the 18th century, "Provincial Administrative Office" (German: Repraesentation und Kammer) and "Provincial Governor’s Office" (German: Landeshauptmannschaft). The last two files date back to the 2nd half of the 18th century. The article also examines two collections of land registers and manuscripts which contain information predominantly from the end of the 16th and from the 17th century.