New sediment cores were recovered from two sites in the central part of Lake Iznik with the overall aim of reconstructing past environmental conditions of the Marmara region. The composite profile presented here, IZN09/LC2&LC3, encompasses the late Pleistocene to Holocene transition (c. 36 ka cal BP) which is the longest lacustrine record in this region obtained to date. A lithostratigraphical and geochronological framework builds the basis to establish a composite section for first inferences on the paleo lake Iznik. The recovered sedimentary record was divided into five stratigraphic units which can be correlated between the different coring locations. The proposed age-depth model is based on eleven C-14 dates (eight radiocarbon-dated levels) and two tephra layers, supported by three OSL ages. The modeled age distribution of the Ca/Ti ratio and magnetic susceptibility express variations in the carbonate accumulation in balance with clastic sediment input.