The Koźle Basin in Poland was radically transformed by aerial bombardment during the Second World War. Today, the region has approximately 6000 well-preserved bomb craters with diameters ranging from 5–15m and depths often exceeding 2m. Combining remote-sensing data and fieldwork with historical accounts, this article analyses these craters, demonstrating that their varied morphologies derive from the weight of the bombs that created them, and on the type and moisture content of the soil on which the bombs fell. Based on their results, the authors issue a call for the official protection of the Koźle landscape, which has particular historical, educational and ecological value.