A first workshop on our Mediterranean Karst Aquifer Map (MEDKAM) and on the special maps on vulnerability, groundwater recharge and water stress took place in Karlsruhe from 10th to 11th February 2020.  Many thanks to our external experts Prof. Zoran Stevanovic (Serbia), Prof. Michel Bakalowicz (France), Dr. Natasa Ravbar (Slovenia), Prof. Andreas Hartmann and Dr. Zhao Chen (Germany) for their valuable ideas and contributions.