The study of both endokarstic systems Bosnek (Vitosha Mountain, Bulgaria) and Wintimdouine (High Atlas Mountain, Morocco) is presented in this work. Both regions are standard for the study of geodynamic processes in Bulgaria and Morocco, and they could be used as geodynamic polygons in the Mediterranean region. The karst is developed in Triassic and Jurassic limestones. The karst processes in both endokarstic systems occur under the conditions of active Quaternary and recent tectonics. A typical structural karst is formed. The present work shows also the results of the comprehensive studies performed in the field of geology, tectonics, geomorpholody, hydrology, climatology, etc., of the karst. It is accented on the genesis and the evolution of the greatest cave systems in Bulgaria (Duhlata cave ý more than 17 km) and Morocco (Wintimdouine cave ý more than 19 km long). Both cave systems are situated in zones with high seismicity, with open surface and sud-surfase paleoseismic disruptions. The karst study and monitoring of its processes has great practical value in Bulgaria and Morocco because they are related to one of the largest urbanized territories ( Pernik and Sofia for Bulgaria, and Agadir for Morocco) and they are protected natural objectives as well.