Tree-ring chronologies are unique archives for various parameters indicating climatic change. The wood structure of trees deposited in river gravel below the water table is well preserved, even after several millennia, and it provides information on a time scale of solar years. During the past 25 years, in the Hohenheim tree-ring laboratory long tree-ring chronologies have been constructed, now reaching back to 11,400 yr dendro B.P.. In this contribution, we demonstrate the evidence for climatic change in the early Holocene, which can be obtained both from botanical properties (e.g. parameters of ring growth) and from the isotopic information recorded in tree rings.