Objectives We examined canopy gap structure and regen-eration patterns at the landscape scale using a combination of remote sensing and field-based surveys. & Methods The study was carried out in the forest reserve of Lom, an old-growth Fagus-Abies-Picea forest located within the Dinaric Alps in the north-western part of Bosnia and Herzegovina. A high-resolution (1-m panchromatic and 4-m multispectral) Kompsat-2 satellite image was orthorectified and classified through an unsupervised pixel-based classifica-tion using an artificial neural network method. & Results This approach allowed the identification of 650 canopy gaps, ranging in size from 32 to 1,776 m 2 . Only 20 intermediate to large gaps (>250 m 2) were identified, and they were mainly present near the perimeter of the reserve. The origin of these large openings was associated with past human-caused disturbances or topographic conditions. The species composition of regeneration within large, human-caused gaps differed markedly from small gaps and non-gap sites in the core area of the reserve. Shade-intolerant species dominated the seedling and sapling layers in large openings. The landscape approach employed in this study confirmed the Handling Editor: Jean Daniel Bontemps Contribution of the co-authors M. Garbarino contributed to the multivariate statistical analysis, the image analyses, and the spatial analysis. E. Borgogno Mondino, remote sensing specialist, contributed to the satellite image pre-processing and classification. E. Lingua contributed to the spatial analysis and related GIS analyses. R. hypothesis that small gaps predominate at Lom, especially within the core area of the reserve.