The quantity and condition of urban greenery directly affect the quality of life of residents and space users. This quality is linked to measures that reduce the negative impact of climate change. It was assumed that urban greenery should not only be protected but also should have its stock increased, which is not easy in a historical, compact structure under statutory conservation. This paper discusses the issue of green areas in the strict city centre of Krakow, a UNESCO World Heritage Site since 1978. The study area includes two medieval towns that had their town charters issued in the 13th and 14th centuries, which together formed a central town and a satellite town. Kazimierz and Stradom were subjected to a detailed investigation. A review of the literature and other sources made it possible to identify changes in the structure of green spaces in terms of chronology and quantity. Changes in the area, accessibility and the legal provisions arising from the various forms of statutory conservation and their consequences were analysed. Multi-criteria analyses of the historical urban structure and the types, forms and potential for introducing greenery into the historical area were also performed. The intention was to strengthen green infrastructure, which is a key element in climate change mitigation.