Old forests that are protected can reduce climatic stress. Nevertheless, they are still affected by long-term warming and extreme weather events, and the question is to what extent. We studied environmental change in five German beech forest landscapes, all of which are part of UNESCO Natural World Heritage Sites and have been out of use since at least 1990. We compared protected core and buffer zones as well as surrounding landscapes using hot-day Land Surface Temperature (LSTHot), Normalized Difference Vegetation Index (NDVISep), climate data, canopy height and forest connectivity.LSTHot increased in all sites and zones, core zones were usually cooler and greener, but these differences were small compared with the overall warming trend. Forest connectivity declined in most sites, hot days generally increased, frost days declined, radiation tended to rise, and precipitation fluctuated strongly among years. The fluctuation of NDVISep reflects disturbances from heatwaves and droughts.The greener, higher elevated, and more connected landscapes were generally cooler, while greater thermal exposure and higher radiation were linked to higher LSTHot. The cooling effect was stronger when radiation was high, suggesting that green canopies were most effective when the potential for surface heating was greatest, likely through evapotranspirative cooling. The German UNESCO beech forests still act as relatively cool refuge areas, yet they are certainly not protected from the regional warming trend. Their future buffering capacity depends not only on continued protection of their core zones, but also on keeping surrounding landscapes as connected, forested, and ecologically functional as possible.