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In earlier studies, the topography and melting dynamics of ice‐cored ridges within marginal zones of the Pleistocene ice sheets were routinely reconstructed based only on conceptual and qualitative models supported by geomorphological, sedimentological and palaeogeographical studies. Here, a novel approach based on detailed structural analysis of two collapse structures affecting Pleistocene kame deposits is presented. The high regularity of the geometry of synclines and related strain fields as well as the patterns of subsidence of the folded strata are all interpreted as evidence of topography of ice‐cored ridges and their melting dynamics. The topography is described in terms of elongation, orientation and cross‐sectional shape of ice‐cored ridges. In turn, the melting dynamics are assessed based on a semi‐quantitative model of different relative rates of backwasting and downwasting. The topography of ice‐cored ridges, derived independently from the morphology of the related supraglacial landforms, is interpreted as an effect of ablation controlled by debris bands within parent ice. The reconstructed ice‐cored ridges are considered to represent the second‐order topographic features within a wide ice‐cored depression. The sedimentary evolution of collapse structures expressed as migration of their hinges/depocentres provides new semi‐quantitative insight into melting dynamics of ice showing the predominance of backwasting over downwasting. This evolution concerns the final stage of de‐icing, which was probably preceded by lowering of the ice‐cored topography and progressive formation of the ice‐cored ridges.

Evaluating the geotourism potential of geological objects is now one of the main directions of geotourism development in Poland. So far, these have been usually carried out for famous and interesting objects, which are situated in physical-geographical regions of great morphological-geological values and are places of high intensity tourism. However, recently more and more attempts have been made to evaluate geotourism potential of geological objects situated in the areas considered unattractive to tourists. This paper reports the results of such an attempt, which has been made in the eastern part of the borderland between two physical-geographical regions of low-intensity tourism, i.e. the Siedlce Upland and Łuków Plain. To evaluate the tourism potential of geological objects, the method of geosite evaluation has been used. The results allowed the author to distinguish the objects of high and unique scientific values, which may be proposed as geosites and a geotourist trail in the study area.