Changes in land use and in the microstructure of the landscape mosaic are most apparent on a local scale. It would not be practicable to evaluate these small-scale changes over the whole area of the Czech Republic. This case study presents a study area of typical intensively exploited region of Northern Bohemia. The analysed time period (1938-1998) includes all the most relevant stages in the recent development of the Czech Republic. Using GIS tools, aerial photographs and maps were interpreted for their land uses in ten-year steps. Values of the following attributes of the landscape structure were analysed and calculated: percentage and distribution of permanent landscape structures (pastures, meadows, forest land, water elements, other forms of permanent vegetation), length of edges, index of landscape heterogeneity, etc. The results show a major decrease in landscape heterogeneity in the period 1938-1988. Both of the main attributes showed a significant decrease - length of edges (-28.4%) and index of landscape heterogeneity (-28.7%). The results also confirm that the socialist period in the development of the Czech Republic brought mostly negative land use and landscape structure changes. The trend was toward a decline of biodiversity and also landscape stability. The study area, which can be described as a highly intensive rural region, shows a decreasing trend in landscape heterogeneity between 1938-1988 similar to that in regions with marginal agricultural conditions.