Within a combined experiment hydrogeological and seismological measurements are undertaken in the area Bursa/Turkey. Seismological equipment continuously monitors the ground motion, the local and regional seismicity (1/2 year). Simultaneously, hydrological key parameters are monitored at artesian wells (bore holes). The aim is to gain an improved description of the earthquake activity near the city of Bursa and a detailed analysis of the hydro-thermal system, i.e. the relation between earthquake activity and pore pressure changes.